Shiziyang Tunnel

Shiziyang Tunnel

Overview
Line	Guangzhou-Shenzhen-Hong Kong
Operation
Constructed	China Railway Group China Railway 12th Bureau Group
Opened	26 December 2011 (2011-12-26)
Technical
Length	5.3 kilometres 5.5 kilometres
No. of tracks	2
Operating speed	250km/h (350km/h designed)

The Shiziyang Tunnel is a high-speed railway tunnel under Shiziyang, the northern part of the Pearl River estuary in China.^[1]

The 10.8 km long tunnel is part of a 140-kilometer (87 mi)-long high-speed line from Guangzhou to Shenzhen and Hong Kong. It is designed for speeds of up to 350 km/h (usually 250 km/h in operation) - the fastest underwater tunnel in the world.^[2] as well as being China's longest underwater tunnel.^[3] This allows rail journeys between Guangzhou and Hong Kong to take only 40 minutes – much faster than the previous 2-hour journey. The Guangzhou-Shenzhen-Hong Kong express rail link is part of a broader expansion of high-speed rail in China; journeys from Beijing to Hong Kong will take only 8 hours.^[4]

Construction began in November 2007, with a budget of CNY2.4 billion;^[5] the tunnel was completed in 2011, and passenger services began on 26 December 2011.^[4] Unusually, the tunnel boring machines were designed to be dismantled inside the tunnel.^[5]

22°52′00″N 113°33′32″E / 22.86669°N 113.55881°E / 22.86669; 113.55881