Tate's Cairn Tunnel is a four-lane road tunnel in Hong Kong. Constructed as part of Route 2, it links Diamond Hill, New Kowloon with Siu Lek Yuen, Sha Tin, New Territories East. It opened on 26 June 1991. Its toll plaza is situated on the Sha Tin side, leading to Tate's Cairn Highway, Sha Lek Highway and various local roads. The tunnel joins the Kwun Tong Bypass and is connected with Lung Cheung Road and Hammer Hill Road and several local roads on the Kowloon side. Tate's Cairn Tunnel is the third longest road tunnel in the New Territories and in Hong Kong, and the second longest over land, with the northbound tube having a length of and southbound tube having a length of , after Tuen Mun–Chek Lap Kok Tunnel (at ) and Lung Shan Tunnel () – It was the longest when it opened. History Construction of the Tate's Cairn Tunnel, begun in July 1988, was carried out by a joint venture between Gammon Construction and Nishimatsu. Nishimatsu built the tunnel and the two ventilation buildings, while Gammon constructed the approach roads and buildings. The tunnel opened to traffic at 8:00 pm on 26June 1991. It was reported that traffic in the Lion Rock Tunnel dropped 20 per cent during the Tate's Cairn Tunnel's first day of operation. The tunnel was formally inaugurated by Governor David Wilson on 1July that year. Franchise model The Tate's Cairn Tunnel is a BOT (build, operate, transfer) infrastructure project funded 100% by the private sector. The BOT franchise was awarded to the Tate's Cairn Tunnel Company Limited for a period of 30 years by the Hong Kong Government in 1988. Under the terms of the BOT, the franchisee is responsible for the construction and operation of the tunnel until the end of the franchise period. During the franchise period, the company was allowed to earn a reasonable but not excessive return through the collection of tolls. The statutory requirements to the company were defined by the Tate's Cairn Tunnel Ordinance. Upon the expiration of franchise at midnight of 11July 2018, the tunnel is now transferred to the government. Tunnel tolls Tolls are collected manually or electronically in both directions at the toll plaza on the Sha Tin side. Notes Tunnel facilities dual-tube, 4-laned 9 manual toll booths and 5 autotoll booth 24 cross passages 160 fire alarms 156 emergency telephones 320 fire