Shiziyang tunnel
The Shiziyang Tunnel is a high-speed railway tunnel under Shiziyang the northern part of the Pearl River estuary in China.
The 10.8 km long tunnel is part of a 140 km high-speed line from Guangzhou to Shenzhen and Hong Kong. It is designed for speeds of up to 350 km/h - the fastest underwater tunnel in the world. as well as being China's longest underwater tunnel. 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.
Construction began in November 2007, with a budget of CNY2.4 billion; the tunnel was completed in 2011, and passenger services began on 26 December 2011. Unusually, the tunnel boring machines were designed to be dismantled inside the tunnel.
Coordinates: 22°52′40″N 113°34′25″E / 22.87778°N 113.57361°E
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