We asked you five quick trivia questions about tunnels. Here are the answers:
- From 1906 to 1982 the longest railway tunnel in the world was in the Alps. What is its name?
The Simplon Tunnel, connecting Brig in Switzerland with Domodossola in Italy. Work started on the first tunnel (19.7 km/12 m 425 yds) in 1898 and finished eight years later; the second tunnel (19.824 km/12 m 560 yds) was built between 1912 and 1921.
- The Channel Tunnel incorporates the longest stretch of undersea tunnel in the world, at 37.9 km (23½ miles). What’s the average thickness of earth between it and the sea bed?
45 metres (148 ft). Approximately 18 million people travelled through the tunnel in 2012 – 10 million in Eurostar trains between London and Paris/Brussels, the rest on Eurotunnel road vehicle shuttles between Cheriton and Sangatte.
- The three tunnels dug for the mass escape from German prisoner-of-war camp Stalag Luft III in March 1944 (The Great Escape) were called Tom, Dick and Harry. Which was actually used for the escape, and how long was it?
Harry, which was 102 m (111 yds) long. It was also nine metres (30 ft) underground and took nearly a year to dig. 76 men escaped through it, but only three made it to neutral territory: two Norwegians reached Sweden, one Dutchman made it to the British Consulate in Spain. Of the 73 recaptured, 50 were murdered by the Gestapo (singly or in pairs) on Hitler’s orders.
- The Marmaray Tunnel opened this month, connecting Europe and Asia. Where?
Istanbul. Taking its name from the Sea of Marmara (to the south of the Bosphorus) and the Turkish word ray (rail), it’s the first railway tunnel between the European and Asian parts of the city and runs from Fatih to Üsküdar. Prime Minister Recep Tayyip Erdoğan rather hyperbolically claimed it would connect London to Beijing – apparently forgetting about the existence of the much more conveniently routed Trans-Siberian Railway.
- The Umeda Exit of the Hanshin Expressway’s Ikeda Route in Osaka incorporates a short tunnel. Why is it unusual?
It goes through a building, the Gate Tower Building in Fukushima-ku. The owners of the property had planned to build a tower block but were thwarted by the plans for the highway, and refused to sell the land to the highway corporation. A compromise was reached whereby the single-lane highway slip road is carried in a tube passing through Floors 5-7 of the building (it’s actually listed as the tenant of those floors on the lobby directory sign!). To minimise noise and vibration, it doesn’t touch the building at any point and is held up by external supports.
How did you get on? Why not let us know?