Kai Tak Tunnel

Construction of the tunnel had started by 1975,[3] but because of the difficulties in digging under the airport runway, it was not complete until 1982. The southern tube opened to two-way traffic at 3:00 pm on 29 June 1982.[4] The second (northern) tube opened on 8 October that year.[5] The Airport Tunnel was the first tunnel in Hong Kong to be toll-free,[2] excluding short underpasses.

With Kai Tak Airport's shutdown in 1998, the Airport Tunnel was no longer fulfilled to its name. The Hong Kong Government announced to rename to Kai Tak Tunnel on 2 March 2006 that the tunnel, effective from 4 May 2006, after several years of consultation with groups including the Kowloon City District Council. The name was changed to commemorate the former Kai Tak International Airport.[6]

The tunnel consists of a pair of tubes of about 7 metres diameter each, 1.26 km long. The southern tube carries west-bound traffic from Kowloon Bay to Ma Tau Kok. A point of interest is that the eastbound tunnel branches off onto Sung Wong Toi Road.[7] It is the only major vehicular tunnel in Hong Kong built entirely by the cut-and-cover technique.[2]

Many major express bus routes of Kowloon Motor Bus and New World First Bus between Kowloon and the eastern end of New Kowloon travel through the Kai Tak Tunnel. Most of them run between the Kwun Tong District or Sai Kung District and Tsim Sha Tsui and Hung Hom. They include 13X, 213X, 224X, 98D, 98P, 14X, 215X, 219X, 296D, 297, 796P. Westbound departures of routes 11X and 28 and peak hour cross harbour tunnel bus route 101X and Hong Kong High Speed Rail feeder bus route W2, also runs through Kai Tak Tunnel. In total, an estimated 60000 vehicles use the tunnel each day.[7]