Bulgaria

Odrysian golden wreath in the National History Museum

Neanderthal remains dating to around 150,000 years ago, or the Middle Paleolithic, are some of the earliest traces of human activity in the lands of modern Bulgaria.[16] Remains from Homo sapiens found there are dated c. 47,000 years BP. This result represents the earliest arrival of modern humans in Europe.[17][18] The Karanovo culture arose circa 6,500 BC and was one of several Neolithic societies in the region that thrived on agriculture.[19] The Copper Age Varna culture (fifth millennium BC) is credited with inventing gold metallurgy.[20][21] The associated Varna Necropolis treasure contains the oldest golden jewellery in the world with an approximate age of over 6,000 years.[22][23] The treasure has been valuable for understanding social hierarchy and stratification in the earliest European societies.[24][25][26]

The Thracians, one of the three primary ancestral groups of modern Bulgarians, appeared on the Balkan Peninsula some time before the 12th century BC.[27][28][29] The Thracians excelled in metallurgy and gave the Greeks the Orphean and Dionysian cults, but remained tribal and stateless.[30] The Persian Achaemenid Empire conquered most of present-day Bulgaria in the 6th century BC and retained control over the region until 479 BC.[31][32] The invasion became a catalyst for Thracian unity, and the bulk of their tribes united under king Teres to form the Odrysian kingdom in the 470s BC.[30][32][33] It was weakened and vassalized by Philip II of Macedon in 341 BC,[34] attacked by Celts in the 3rd century,[35] and finally became a province of the Roman Empire in AD 45.[36]

By the end of the 1st century AD, Roman governance was established over the entire Balkan Peninsula and Christianity began spreading in the region around the 4th century.[30] The Gothic Bible—the first Germanic language book—was created by Gothic bishop Ulfilas in what is today northern Bulgaria around 381.[37] The region came under Byzantine control after the fall of Rome in 476. The Byzantines were engaged in prolonged warfare against Persia and could not defend their Balkan territories from barbarian incursions.[38] This enabled the Slavs to enter the Balkan Peninsula as marauders, primarily through an area between the Danube River and the Balkan Mountains known as Moesia.[39] Gradually, the interior of the peninsula became a country of the South Slavs, who lived under a democracy.[40][41] The Slavs assimilated the partially Hellenized, Romanized, and Gothicized Thracians in the rural areas.[42][43][44][45]

Krum feasts with nobles of his court following the victory over Nicephorus I

Not long after the Slavic incursion, Moesia was once again invaded, this time by the Bulgars under Khan Asparukh.[46] Their horde was a remnant of Old Great Bulgaria, an extinct tribal confederacy situated north of the Black Sea in what is now Ukraine and southern Russia. Asparukh attacked Byzantine territories in Moesia and conquered the Slavic tribes there in 680.[28] A peace treaty with the Byzantine Empire was signed in 681, marking the foundation of the First Bulgarian Empire. The minority Bulgars formed a close-knit ruling caste.[47]

Succeeding rulers strengthened the Bulgarian state throughout the 8th and 9th centuries. Krum introduced a written code of law[48] and checked a major Byzantine incursion at the Battle of Pliska, in which Byzantine emperor Nicephorus I was killed.[49] Boris I abolished paganism in favour of Eastern Orthodox Christianity in 864. The conversion was followed by a Byzantine recognition of the Bulgarian church[50] and the adoption of the Cyrillic alphabet, developed in the capital, Preslav.[51] The common language, religion and script strengthened central authority and gradually fused the Slavs and Bulgars into a unified people speaking a single Slavic language.[52][51] A golden age began during the 34-year rule of Simeon the Great, who oversaw the largest territorial expansion of the state.[53]

After Simeon's death, Bulgaria was weakened by wars with Magyars and Pechenegs and the spread of the Bogomil heresy.[52][54] Preslav was seized by the Byzantine army in 971 after consecutive Rus' and Byzantine invasions.[52] The empire briefly recovered from the attacks under Samuil,[55] but this ended when Byzantine emperor Basil II defeated the Bulgarian army at Klyuch in 1014. Samuil died shortly after the battle,[56] and by 1018 the Byzantines had conquered the First Bulgarian Empire.[57] After the conquest, Basil II prevented revolts by retaining the rule of local nobility, integrating them in Byzantine bureaucracy and aristocracy, and relieving their lands of the obligation to pay taxes in gold, allowing tax in kind instead.[58][59] The Bulgarian Patriarchate was reduced to an archbishopric, but retained its autocephalous status and its dioceses.[59][58]

The walls of Tsarevets fortress in Veliko Tarnovo, the capital of the second empire

Byzantine domestic policies changed after Basil's death and a series of unsuccessful rebellions broke out, the largest being led by Peter Delyan. The empire's authority declined after a catastrophic military defeat at Manzikert against Seljuk invaders, and was further disturbed by the Crusades. This prevented Byzantine attempts at Hellenisation and created fertile ground for further revolt. In 1185 Asen dynasty nobles Ivan Asen I and Peter IV organized a major uprising and succeeded in re-establishing the Bulgarian state. Ivan Asen and Peter laid the foundations of the Second Bulgarian Empire with its capital at Tarnovo.[60]

Kaloyan, the third of the Asen monarchs, extended his dominion to Belgrade and Ohrid. He acknowledged the spiritual supremacy of the pope and received a royal crown from a papal legate.[61] The empire reached its zenith under Ivan Asen II (1218–1241), when its borders expanded as far as the coast of Albania, Serbia and Epirus, while commerce and culture flourished.[61][60] Ivan Asen's rule was also marked by a shift away from Rome in religious matters.[62]

The Asen dynasty became extinct in 1257. Internal conflicts and incessant Byzantine and Hungarian attacks followed, enabling the Mongols to establish suzerainty over the weakened Bulgarian state.[61][62] In 1277, swineherd Ivaylo led a great peasant revolt that expelled the Mongols from Bulgaria and briefly made him emperor.[63][60] He was overthrown in 1280 by the feudal landlords,[63] whose factional conflicts caused the Second Bulgarian Empire to disintegrate into small feudal dominions by the 14th century.[60] These fragmented rump states—two tsardoms at Vidin and Tarnovo and the Despotate of Dobrudzha—became easy prey for a new threat arriving from the Southeast: the Ottoman Turks.[61]

The Battle of Nicopolis in 1396 marked the end of medieval Bulgarian statehood

The Ottomans were employed as mercenaries by the Byzantines in the 1340s but later became invaders in their own right.[64] Sultan Murad I took Adrianople from the Byzantines in 1362; Sofia fell in 1382, followed by Shumen in 1388.[64] The Ottomans completed their conquest of Bulgarian lands in 1393 when Tarnovo was sacked after a three-month siege and the Battle of Nicopolis which brought about the fall of the Vidin Tsardom in 1396. Sozopol was the last Bulgarian settlement to fall, in 1453.[65] The Bulgarian nobility was subsequently eliminated and the peasantry was enserfed to Ottoman masters,[64] while much of the educated clergy fled to other countries.[66]

Bulgarians were subjected to heavy taxes (including devshirme, or blood tax), their culture was suppressed,[66] and they experienced partial Islamisation.[67] Ottoman authorities established a religious administrative community called the Rum Millet, which governed all Orthodox Christians regardless of their ethnicity.[68] Most of the local population then gradually lost its distinct national consciousness, identifying only by its faith.[69][70] The clergy remaining in some isolated monasteries kept their ethnic identity alive, enabling its survival in remote rural areas,[71] and in the militant Catholic community in the northwest of the country.[72]

As Ottoman power began to wane, Habsburg Austria and Russia saw Bulgarian Christians as potential allies. The Austrians first backed an uprising in Tarnovo in 1598, then a second one in 1686, the Chiprovtsi Uprising in 1688 and finally Karposh's Rebellion in 1689.[73] The Russian Empire also asserted itself as a protector of Christians in Ottoman lands with the Treaty of Küçük Kaynarca in 1774.[73]

The Russo-Bulgarian defence of Shipka Pass in 1877

The Western European Enlightenment in the 18th century influenced the initiation of a national awakening of Bulgaria.[64] It restored national consciousness and provided an ideological basis for the liberation struggle, resulting in the 1876 April Uprising. Up to 30,000 Bulgarians were killed as Ottoman authorities put down the rebellion. The massacres prompted the Great Powers to take action.[74] They convened the Constantinople Conference in 1876, but their decisions were rejected by the Ottomans. This allowed the Russian Empire to seek a military solution without risking confrontation with other Great Powers, as had happened in the Crimean War.[74] In 1877 Russia declared war on the Ottomans and defeated them with the help of Bulgarian rebels, particularly during the crucial Battle of Shipka Pass which secured Russian control over the main road to Constantinople.[75][76]

The Treaty of San Stefano was signed on 3 March 1878 by Russia and the Ottoman Empire. It was to set up an autonomous Bulgarian principality spanning Moesia, Macedonia and Thrace, roughly on the territories of the Second Bulgarian Empire,[77][78] and this day is now a public holiday called National Liberation Day.[79] The other Great Powers immediately rejected the treaty out of fear that such a large country in the Balkans might threaten their interests. It was superseded by the Treaty of Berlin, signed on 13 July. It provided for a much smaller state, the Principality of Bulgaria, only comprising Moesia and the region of Sofia, and leaving large populations of ethnic Bulgarians outside the new country.[77][80] This significantly contributed to Bulgaria's militaristic foreign affairs approach during the first half of the 20th century.[81]

Borders of Bulgaria according to the preliminary Treaty of San Stefano

The Bulgarian principality won a war against Serbia and incorporated the semi-autonomous Ottoman territory of Eastern Rumelia in 1885, proclaiming itself an independent state on 5 October 1908.[82] In the years following independence, Bulgaria increasingly militarized and was often referred to as "the Balkan Prussia".[83] It became involved in three consecutive conflicts between 1912 and 1918—two Balkan Wars and World War I. After a disastrous defeat in the Second Balkan War, Bulgaria again found itself fighting on the losing side as a result of its alliance with the Central Powers in World War I. Despite fielding more than a quarter of its population in a 1,200,000-strong army[84][85] and achieving several decisive victories at Doiran and Monastir, the country capitulated in 1918. The war resulted in significant territorial losses and a total of 87,500 soldiers killed.[86] More than 253,000 refugees from the lost territories immigrated to Bulgaria from 1912 to 1929,[87] placing additional strain on the already ruined national economy.[88]

Tsar Boris III

The resulting political unrest led to the establishment of a royal authoritarian dictatorship by Tsar Boris III (1918–1943). Bulgaria entered World War II in 1941 as a member of the Axis but declined to participate in Operation Barbarossa and saved its Jewish population from deportation to concentration camps.[89] The sudden death of Boris III in mid-1943 pushed the country into political turmoil as the war turned against Germany, and the communist guerrilla movement gained momentum. The government of Bogdan Filov subsequently failed to achieve peace with the Allies. Bulgaria did not comply with Soviet demands to expel German forces from its territory, resulting in a declaration of war and an invasion by the USSR in September 1944.[90] The communist-dominated Fatherland Front took power, ended participation in the Axis and joined the Allied side until the war ended.[91] Bulgaria suffered little war damage and the Soviet Union demanded no reparations. But all wartime territorial gains, with the notable exception of Southern Dobrudzha, were lost.[92]

Georgi Dimitrov, leader of the Bulgarian Communist Party from 1946 to 1949

The left-wing coup d'état of 9 September 1944 led to the abolition of the monarchy and the executions of some 1,000–3,000 dissidents, war criminals, and members of the former royal elite.[93][94][95] But it was not until 1946 that a one-party people's republic was instituted following a referendum.[96] It fell into the Soviet sphere of influence under the leadership of Georgi Dimitrov (1946–1949), who established a repressive, rapidly industrializing Stalinist state.[92] By the mid-1950s standards of living rose significantly and political repressions eased.[97][98] The Soviet-style planned economy saw some experimental market-oriented policies emerging under Todor Zhivkov (1954–1989).[99] Compared to wartime levels, national GDP increased five-fold and per capita GDP quadrupled by the 1980s,[100] although severe debt spikes took place in 1960, 1977 and 1980.[101] Zhivkov's daughter, Lyudmila, bolstered national pride by promoting Bulgarian heritage, culture and arts worldwide.[102] Facing declining birth rates among the ethnic Bulgarian majority, in 1984 Zhivkov's government forced the minority ethnic Turks to adopt Slavic names in an attempt to erase their identity and assimilate them.[103] These policies resulted in the emigration of some 300,000 ethnic Turks to Turkey.[104][105]

The Communist Party was forced to give up its political monopoly on 10 November 1989 under the influence of the Revolutions of 1989. Zhivkov resigned and Bulgaria embarked on a transition to a parliamentary democracy.[106] The first free elections in June 1990 were won by the Communist Party, now rebranded as the Bulgarian Socialist Party.[107] A new constitution that provided for a relatively weak elected president and for a prime minister accountable to the legislature was adopted in July 1991.[108] The new system initially failed to improve living standards or create economic growth—the average quality of life and economic performance remained lower than under communism well into the early 2000s.[109] After 2001 economic, political and geopolitical conditions improved greatly,[110] and Bulgaria achieved high Human Development status in 2003.[111] It became a member of NATO in 2004[112] and participated in the War in Afghanistan. After several years of reforms it joined the European Union and single market in 2007 despite Brussels' concerns about government corruption.[113] Bulgaria hosted the 2018 Presidency of the Council of the European Union at the National Palace of Culture in Sofia.[114] The 2020–2021 Bulgarian protests were triggered on 9 July 2020 when the Presidency of Bulgaria was raided by police and prosecutors as a result of a long-lasting conflict between the prime minister Boyko Borisov and the president Rumen Radev.[115]

Lacerta viridis in Ropotamo, one of Bulgaria's 16 biosphere reserves

The interaction of climatic, hydrological, geological and topographical conditions has produced a relatively wide variety of plant and animal species.[123] Bulgaria's biodiversity, one of the richest in Europe,[124] is conserved in three national parks, 11 nature parks, 10 biosphere reserves and 565 protected areas.[125][126][127] Ninety-three of the 233 mammal species of Europe are found in Bulgaria, along with 49% of butterfly and 30% of vascular plant species.[128] Overall, 41,493 plant and animal species are present.[128] Larger mammals with sizable populations include deer (106,323 individuals), wild boars (88,948), jackals (47,293) and foxes (32,326). Partridges number some 328,000 individuals, making them the most widespread gamebird.[129] A third of all nesting birds in Bulgaria can be found in Rila National Park, which also hosts Arctic and alpine species at high altitudes.[130] Flora includes more than 3,800 vascular plant species of which 170 are endemic and 150 are considered endangered.[123] A checklist of larger fungi in Bulgaria by the Institute of Botany identifies more than 1,500 species.[131] More than 35% of the land area is covered by forests.[132]

In 1998, the Bulgarian government adopted the National Biological Diversity Conservation Strategy, a comprehensive programme seeking the preservation of local ecosystems, protection of endangered species and conservation of genetic resources.[133] Bulgaria has some of the largest Natura 2000 areas in Europe covering 33.8% of its territory.[134] It also achieved its Kyoto Protocol objective of reducing carbon dioxide emissions by 30% from 1990 to 2009.[135]

Bulgaria ranks 30th in the 2018 Environmental Performance Index, but scores low on air quality.[136] Particulate levels are the highest in Europe,[137] especially in urban areas affected by automobile traffic and coal-based power stations.[138][139] One of these, the lignite-fired Maritsa Iztok-2 station, is causing the highest damage to health and the environment in the European Union.[140] Pesticide use in agriculture and antiquated industrial sewage systems produce extensive soil and water pollution.[141] Water quality began to improve in 1998 and has maintained a trend of moderate improvement. Over 75% of surface rivers meet European standards for good quality.[142]

Bulgaria has a civil law legal system.[164] The judiciary is overseen by the Ministry of Justice. The Supreme Administrative Court and the Supreme Court of Cassation are the highest courts of appeal and oversee the application of laws in subordinate courts.[144] The Supreme Judicial Council manages the system and appoints judges. The legal system is regarded by both domestic and international observers as one of Europe's most inefficient due to pervasive lack of transparency and corruption.[165][166][167][168][169] Law enforcement is carried out by organisations mainly subordinate to the Ministry of the Interior.[170] The General Directorate of National Police (GDNP) combats general crime and maintains public order.[171] GDNP fields 26,578 police officers in its local and national sections.[172] The bulk of criminal cases are transport-related, followed by theft and drug-related crime; homicide rates are low.[173] The Ministry of the Interior also heads the Border Police Service and the National Gendarmerie—a specialized branch for anti-terrorist activity, crisis management and riot control. Counterintelligence and national security are the responsibility of the State Agency for National Security.[174]

Bulgaria is a unitary state.[175] Since the 1880s, the number of territorial management units has varied from seven to 26.[176] Between 1987 and 1999 the administrative structure consisted of nine provinces (oblasti, singular oblast). A new administrative structure was adopted in parallel with the decentralization of the economic system.[177] It includes 27 provinces and a metropolitan capital province (Sofia-Grad). All areas take their names from their respective capital cities. The provinces are subdivided into 265 municipalities. Municipalities are run by mayors, who are elected to four-year terms, and by directly elected municipal councils. Bulgaria is a highly centralized state where the Council of Ministers directly appoints regional governors and all provinces and municipalities are heavily dependent on it for funding.[144]

Blagoevgrad Burgas Dobrich Gabrovo Haskovo Kardzhali Kyustendil Lovech Montana Pazardzhik Pernik Pleven Plovdiv Razgrad Ruse Shumen Silistra Sliven Smolyan Sofia Province Stara Zagora Targovishte Varna Veliko Tarnovo Vidin Vratsa Yambol

Bulgaria became a member of the United Nations in 1955 and since 1966 has been a non-permanent member of the Security Council three times, most recently from 2002 to 2003.[179] It was also among the founding nations of the Organization for Security and Co-operation in Europe (OSCE) in 1975. Euro-Atlantic integration has been a priority since the fall of communism, although the communist leadership also had aspirations of leaving the Warsaw Pact and joining the European Communities by 1987.[180][181] Bulgaria signed the European Union Treaty of Accession on 25 April 2005,[182] and became a full member of the European Union on 1 January 2007.[113] In addition, it has a tripartite economic and diplomatic collaboration with Romania and Greece,[183] good ties with China[184] and Vietnam[185] and a historical relationship with Russia.[186][187][188][189]

Mikoyan MiG-29 jet fighters of the Bulgarian Air Force

Bulgaria deployed significant numbers of both civilian and military advisors in Soviet-allied countries like Nicaragua[190] and Libya during the Cold War.[191] The first deployment of foreign troops on Bulgarian soil since World War II occurred in 2001, when the country hosted six KC-135 Stratotanker aircraft and 200 support personnel for the war effort in Afghanistan.[25] International military relations were further expanded with accession to NATO in March 2004[112] and the US-Bulgarian Defence Cooperation Agreement signed in April 2006. Bezmer and Graf Ignatievo air bases, the Novo Selo training range, and a logistics centre in Aytos subsequently became joint military training facilities cooperatively used by the United States and Bulgarian militaries.[192][193] Despite its active international defence collaborations, Bulgaria ranks as among the most peaceful countries globally, tying 6th alongside Iceland regarding domestic and international conflicts, and 26th on average in the Global Peace Index.[163]

Domestic defence is the responsibility of the all-volunteer Bulgarian armed forces, composed of land forces, navy and an air force. The land forces consist of two mechanized brigades and eight independent regiments and battalions; the air force operates 106 aircraft and air defence systems in six air bases, and the navy operates various ships, helicopters and coastal defence weapons.[194] Active troops dwindled from 152,000 in 1988[195] to 31,300 in 2017, supplemented by 3,000 reservists and 16,000 paramilitary.[196] Inventory is mostly made up of Soviet equipment like Mikoyan MiG-29 and Sukhoi Su-25 jets,[197] S-300PT air defence systems[198] and SS-21 Scarab short-range ballistic missiles.[199]

Tree-map of Bulgarian exports in 2016

The labour force is 3.36 million people,[240] of whom 6.8% are employed in agriculture, 26.6% in industry and 66.6% in the services sector.[241] Extraction of metals and minerals, production of chemicals, machine building, steel, biotechnology, tobacco, food processing and petroleum refining are among the major industrial activities.[242][243][244] Mining alone employs 24,000 people and generates about 5% of the country's GDP; the number of employed in all mining-related industries is 120,000.[245][246] Bulgaria is Europe's fifth-largest coal producer.[246][247] Local deposits of coal, iron, copper and lead are vital for the manufacturing and energy sectors.[248] The main destinations of Bulgarian exports outside the EU are Turkey, China and the United States, while Russia and Turkey are by far the largest import partners. Most of the exports are manufactured goods, machinery, chemicals, fuel products and food.[249] Two-thirds of food and agricultural exports go to OECD countries.[250]

Although cereal and vegetable output dropped by 40% between 1990 and 2008,[251] output in grains has since increased, and the 2016–2017 season registered the biggest grain output in a decade.[252][253] Maize, barley, oats and rice are also grown. Quality Oriental tobacco is a significant industrial crop.[254] Bulgaria is also the largest producer globally of lavender and rose oil, both widely used in fragrances.[25][255][256][257] Within the services sector, tourism is a significant contributor to economic growth. Sofia, Plovdiv, Veliko Tarnovo, coastal resorts Albena, Golden Sands and Sunny Beach and winter resorts Bansko, Pamporovo and Borovets are some of the locations most visited by tourists.[258][259] Most visitors are Romanian, Turkish, Greek and German.[260] Tourism is additionally encouraged through the 100 Tourist Sites system.[261]

Spending on research and development amounts to 0.78% of GDP,[262] and the bulk of public R&D funding goes to the Bulgarian Academy of Sciences (BAS).[263] Private businesses accounted for more than 73% of R&D expenditures and employed 42% of Bulgaria's 22,000 researchers in 2015.[264] The same year, Bulgaria ranked 39th out of 50 countries in the Bloomberg Innovation Index, the highest score being in education (24th) and the lowest in value-added manufacturing (48th).[265] Chronic government underinvestment in research since 1990 has forced many professionals in science and engineering to leave Bulgaria.[266]

The launch of BulgariaSat-1 by SpaceX

Despite the lack of funding, research in chemistry, materials science and physics remains strong.[263] Antarctic research is actively carried out through the St. Kliment Ohridski Base on Livingston Island in Western Antarctica.[267][268] The information and communication technologies (ICT) sector generates three per cent of economic output and employs 40,000[269] to 51,000 software engineers.[270] Bulgaria was known as a "Communist Silicon Valley" during the Soviet era due to its key role in COMECON computing technology production.[271] The country is a regional leader in high performance computing: it operates Avitohol, the most powerful supercomputer in Southeast Europe, and will host one of the eight petascale EuroHPC supercomputers.[272][273]

Bulgaria has made numerous contributions to space exploration.[274] These include two scientific satellites, more than 200 payloads and 300 experiments in Earth orbit, as well as two cosmonauts since 1971.[274] Bulgaria was the first country to grow wheat and vegetables in space with its Svet greenhouses on the Mir space station.[275][276] It was involved in the development of the Granat gamma-ray observatory[277] and the Vega program, particularly in modelling trajectories and guidance algorithms for both Vega probes.[278][279] Bulgarian instruments have been used in the exploration of Mars, including a spectrometer that took the first high quality spectroscopic images of Martian moon Phobos with the Phobos 2 probe.[274][277] Cosmic radiation en route to and around the planet has been mapped by Liulin-ML dosimeters on the ExoMars TGO.[280] Variants of these instruments have also been fitted on the International Space Station and the Chandrayaan-1 lunar probe.[281][282] Another lunar mission, SpaceIL's Beresheet, was also equipped with a Bulgarian-manufactured imaging payload.[283] Bulgaria's first geostationary communications satellite—BulgariaSat-1—was launched by SpaceX in 2017.[284]

Trakia motorway

Telephone services are widely available, and a central digital trunk line connects most regions.[285] Vivacom (BTC) serves more than 90% of fixed lines and is one of the three operators providing mobile services, along with A1 and Telenor.[286][287] Internet penetration stood at 66.8% of the population aged 16–74 and 75.1% of households, in 2019.[288][289]

Bulgaria's strategic geographic location and well-developed energy sector make it a key European energy centre despite its lack of significant fossil fuel deposits.[290] Thermal power plants generate 48.9% of electricity, followed by nuclear power from the Kozloduy reactors (34.8%) and renewable sources (16.3%).[291] Equipment for a second nuclear power station at Belene has been acquired, but the fate of the project remains uncertain.[292] Installed capacity amounts to 12,668 MW, allowing Bulgaria to exceed domestic demand and export energy.[293]

The national road network has a total length of 19,512 kilometres (12,124 mi),[294] of which 19,235 kilometres (11,952 mi) are paved. Railroads are a major mode of freight transportation, although highways carry a progressively larger share of freight. Bulgaria has 6,238 kilometres (3,876 mi) of railway track[285] and currently a total of 81 kilometres (50 miles) of high-speed lines are in operation.[295][296] Rail links are available with Romania, Turkey, Greece, and Serbia, and express trains serve direct routes to Kyiv, Minsk, Moscow and Saint Petersburg.[297] Sofia and Plovdiv are the country's air travel hubs, while Varna and Burgas are the principal maritime trade ports.[285]

More than three-quarters of Bulgarians subscribe to Eastern Orthodoxy.[339] Sunni Muslims are the second-largest religious community and constitute 10% of Bulgaria's overall religious makeup, although a majority of them are not observant and find the use of Islamic veils in schools unacceptable.[340] Less than 3% of the population are affiliated with other religions and 11.8% are irreligious or do not self-identify with a religion.[339] The Bulgarian Orthodox Church gained autocephalous status in AD 927,[341][342] and has 12 dioceses and over 2,000 priests.[343] Bulgaria is a secular state with guaranteed religious freedom by constitution, but Orthodoxy is designated as a "traditional" religion.[344]

Grigor Dimitrov at the 2015 Italian Open

Bulgaria appeared at the first modern Olympic games in 1896, when it was represented by gymnast Charles Champaud.[379] Since then, Bulgarian athletes have won 52 gold, 89 silver, and 83 bronze medals,[380] ranking 25th in the all-time medal table. Weight-lifting is a signature sport of Bulgaria. Coach Ivan Abadzhiev developed innovative training practices that have produced many Bulgarian world and Olympic champions in weight-lifting since the 1980s.[381] Bulgarian athletes have also excelled in wrestling, boxing, gymnastics, volleyball and tennis.[381] Stefka Kostadinova is the reigning world record holder in the women's high jump at 2.09 metres (6 feet 10 inches), achieved during the 1987 World Championships.[382] Grigor Dimitrov is the first Bulgarian tennis player in the Top 3 ATP Rankings.[383]

Football is the most popular sport in the country by a substantial margin. The national football team's best performance was a semi-final at the 1994 FIFA World Cup, when the squad was spearheaded by forward Hristo Stoichkov.[381] Stoichkov is the most successful Bulgarian player of all time; he was awarded the Golden Boot and the Golden Ball and was considered one of the best in the world while playing for FC Barcelona in the 1990s.[384][385] CSKA and Levski, both based in Sofia,[381] are the most successful clubs domestically and long-standing rivals.[386] Ludogorets is remarkable for having advanced from the local fourth division to the 2014–15 UEFA Champions League group stage in a mere nine years.[387] Placed 39th in 2018, it is Bulgaria's highest-ranked club in UEFA.[388]