A railway tunnel under the English Channel, linking the coasts of England and France, opened in 1994 and 49 km (31 miles) long.
海峡隧道（穿越英吉利海峡的铁路隧道，连接英国与法国海岸，1994年开通，全长49公里，即31英里）
Definition of Channel Tunnel in US English:
Channel Tunnel
proper noun
A railroad tunnel under the English Channel that extends for 31 miles (49 km) and links England and France. The tunnel (popularly called the Chunnel) opened in 1994 after eight years of construction to link Holywell, near Folkestone, England, and Sangatte, near Calais, France.