Interstate 80 in New Jersey

View east along I-80 just after entering New Jersey within the Delaware Water Gap National Recreation Area

I-80 enters Hardwick Township, Warren County from Pennsylvania on the Delaware Water Gap Toll Bridge over the Delaware River, maintained by the Delaware River Joint Toll Bridge Commission (DRJTBC).[1] In addition to carrying I-80, this bridge also carries the Appalachian Trail over the Delaware River. From this point, the four-lane freeway heads south along the east bank of the river through the Delaware Water Gap, immediately reaching a westbound exit and eastbound entrance for Old Mine Road.[1][4] Now maintained by NJDOT, the road makes a sharp turn to the east and comes to a U-turn ramp in both directions that also has access to the Appalachian Trail.[1] NJDOT has proposed a controversial rock wall along the stretch to handle rock slides.[5] The highway heads south again and enters Knowlton Township, where it comes to another set of U-turn ramps that also includes a weigh station in the eastbound direction. After turning southeast and leaving the Delaware Water Gap, the road has a westbound right-in/right-out for Hainesburg Road before crossing under the abandoned Delaware River Viaduct of the Lackawanna Cutoff. East of the viaduct, I-80 widens to six lanes and reaches a complex interchange with the western terminus of US 46, Route 94, and Decatur Street in Columbia, where development near the route increases. After this interchange, the freeway turns east away from the Delaware River and crosses over Paulins Kill before it continues through wooded and hilly areas containing some farms, with the eastbound direction widening from three to four lanes and the highway median also widens. A scenic overlook of the Delaware Water Gap is located in the westbound direction while a rest area is located in the eastbound direction.[1][4]

I-80 westbound at CR 521 exit in Hope Township

Upon crossing into Blairstown Township, the eastbound direction narrows down to three lanes.[1] In Hope Township, I-80 reaches an interchange with County Route 521 (CR 521) that also provides access to CR 519 and the Land of Make Believe amusement park.[1][4] The highway widens to eight lanes briefly after this interchange before narrowing to six lanes. In Frelinghuysen Township, the freeway carries four lanes eastbound and three lanes westbound. Upon coming into Allamuchy Township, I-80 has six lanes before gaining a fourth eastbound lane as it comes to the CR 517 exit.[1] This exit gives the highway access to Allamuchy Mountain State Park.[4] Following this, the road runs through densely forested areas of Allamuchy Mountain State Park, coming to two pairs of rest areas with no facilities in both directions. The eastbound direction becomes three lanes again before the road passes through Byram Township in Sussex County.[1][4]

I-80 westbound at US 46 exit in Roxbury Township

Upon crossing the Musconetcong River, I-80 enters Mount Olive Township in Morris County and passes through more woodland with a narrower median. The road comes to a trumpet interchange with US 206 and forms a concurrency with that route as it bypasses Netcong to the south. After turning southeast and passing near suburban business parks, the highway crosses over NJ Transit’s Morristown Line/Montclair-Boonton Line and reaches a partial interchange with US 46.[1][4] This interchange has only a westbound exit and eastbound entrance. The freeway crosses a small corner of Netcong and Mount Olive Township again before continuing into Roxbury Township, where it comes to a modified cloverleaf interchange.[1] At this interchange, Route 183 heads north into Netcong and US 206 splits from I-80 by heading south. The road continues through wooded areas containing some suburban development as it comes to the CR 631 interchange, which also provides access to eastbound US 46.[1][4] The road crosses the NJ Transit line again and parallels it a short distance to the north as it comes into Mount Arlington and reaches the Howard Boulevard exit, serving Mount Arlington station.[1] I-80 continues back into Roxbury Township and comes to a westbound truck rest area with the eastbound one being abandoned.[1][6][7] After this, the road heads farther north of the railroad tracks and briefly passes through Jefferson Township and Rockaway Township before continuing into Wharton. Here, the freeway has an eastbound exit to CR 634 that provides access to Route 15 before it reaches the interchange with Route 15 proper that lacks an eastbound exit.[1]

I-80 westbound past Howard Boulevard interchange in Mount Arlington

The highway continues back into Rockaway Township as it widens to eight lanes and comes to the CR 661 exit near the Rockaway Townsquare shopping mall. Suburban development near the highway becomes more dense at this point as I-80 briefly passes through a corner of Rockaway before coming to the interchange with CR 513 in Rockaway Township.[1][4] The freeway passes over the Dover and Rockaway River Railroad's Dover and Rockaway Branch and turns southeast here into Denville. In the center of Denville, it has an eastbound exit and westbound entrance serving US 46 that also provides access to Route 53. There is a westbound exit and eastbound entrance serving both US 46 and Route 53 as the road begins to turn more to the east. I-80 turns south and crosses the Montclair-Boonton Line for a third time before it enters Parsippany-Troy Hills.[1] The highway makes a turn east as it comes into an area of business parks, with the median widening before an interchange serving US 202 and CR 654.[1][4] The median narrows again before I-80 reaches the I-287 interchange that also has movements to US 46 and Smith Road to and from the east.[1]

I-80 eastbound at the exit for US 46 in Wayne

Past I-287, I-80 gains local-express lanes with a 2-3-3-2 configuration.[1] The road continues past more commercial areas, with the local lanes having an eastbound exit and westbound entrance at CR 637.[1][4] After this, there is a large interchange with US 46 and the western terminus of I-280, at which point the local-express lanes end.[1] From this point, I-80 continues east through wooded areas as a six-lane freeway, crossing into Montville.[1][4] In Montville, there is a partial interchange providing access to Hook Mountain Road.[1] After a turn to the northeast, the highway comes into Fairfield Township, Essex County, continuing through wooded surroundings as it heads north before turning east. Development near the road increases as it comes to the westbound exit and eastbound entrance with CR 613.[1][4]

I-80 eastbound approaching the Route 17 interchange in Hackensack

After crossing the Passaic River again, I-80 enters Wayne in Passaic County.[1] Here, the road passes under the Montclair-Boonton Line before coming to the Spaghetti Junction with Route 23 and US 46 near the Willowbrook Mall. At this point, the freeway widens to eight lanes and continues into Totowa, passing near more commercial areas and over a Norfolk Southern railroad line as it comes to an interchange with CR 642 that has access to and from the west.[1][4] A short distance later, there is a westbound exit and eastbound entrance serving Route 62 and CR 646.[1] I-80 crosses the Passaic River a third time and enters Woodland Park, where it turns to the northeast past suburban neighborhoods and reaches an interchange serving CR 636.[1][4] Passing to the north of Garret Mountain Reservation, the freeway enters Paterson and turns east into urban areas as it comes to the interchange at the Route 19 freeway. After Route 19, I-80 runs above Paterson on a viaduct, crossing over NJ Transit's Main Line before coming to the exit for CR 649 (Madison Avenue). The road returns to ground level near urban neighborhoods as it comes to an eastbound exit and westbound entrance serving Market Street.[1][4] A short distance later, I-80 encounters Route 20 at an interchange.[1]

Eastern terminus of I-80 in Bergen County viewed from an airplane

After a fourth crossing of the Passaic River, I-80 comes into Elmwood Park in Bergen County. Immediately after the river, the highway reaches the CR 507 exit.[1] It continues near suburban neighborhoods, coming to a bridge over New York, Susquehanna and Western Railway's (NYSW) New Jersey Subdivision line, and passes over NJ Transit's Bergen County Line as it comes to an interchange with the Garden State Parkway on the border of Elmwood Park and Saddle Brook that also has connections to CR 67.[1][4] At the Garden State Parkway, I-80 gains a 2-2 local-express lane configuration eastbound while the westbound direction carries four lanes. The next interchange along the road is with CR 79, and is a westbound entrance and an eastbound exit accessible from the local lanes. The freeway passes over the NYSW line again and turns south along the west bank of the Saddle River, eventually crossing it into Lodi.[1] Immediately after, there is a diamond interchange at Riverview Avenue that provides access to Route 4 and Route 17. Heading southeast, I-80 passes over NYSW's Lodi Branch line and comes to an interchange at Route 17, which provides access to US 46 to the south, Route 4 to the north, and various local roads. At this point, I-80 runs between the travel lanes of Route 17 as it continues into Hackensack. Past Route 17, I-80 gains a 3-2-2-3 local-express lane configuration and crosses NJ Transit's Pascack Valley Line before passing through industrial parks and running through a small part of South Hackensack.[1][4] Here, there is an interchange to Green Street before the highway comes into Teterboro. Turning east, the freeway runs through South Hackensack before entering Hackensack, where an exit provides access to CR 124 (Hudson Street).[1] The road passes near neighborhoods before crossing the Hackensack River into Ridgefield Park, where it passes over NYSW's New Jersey Subdivision line and CSX's River Subdivision line before there is an exit for 2nd Street.[1][4] The freeway passes through a corner of Bogota before it continues into Teaneck.[1][4] In Teaneck, I-80 reaches its eastern terminus at the interchange with I-95 (the New Jersey Turnpike). From here, one can head southbound on I-95 and the turnpike towards Newark, or head northbound towards the George Washington Bridge and New York City.[4]