Some of them are.
The Channel Tunnel is 50.45 km or 31.35 miles.
The Hoosac Tunnel is 4.75 miles in length or 7.64 km long.
The M5 East Tunnel in Syndey is 8.55 km long.
Eurotunnel is the company which owns and operates the Channel Tunnel between England and France.The Channel Tunnel is 50.5 Km (31.4 miles) long, of which 37.9 Km (23.5 miles) is underwater.
16,9 km
distance
The tunnel is 50.5 km long (31.4 miles). of which 37.9 km. (23.5 miles) is below the seabed.
Eurotunnel is the name of the company which owns and operates the Channel Tunnel, as well as other business interests. The Channel Tunnel runs between Folkestone and Sangatte, near Calais. Channel Tunnel length is about 50 Km of which 38 Km are below the water. 50.5 km (31.4 mi)
The Channel Tunnel connects England and France, and it is located underneath the English Channel. The Channel Tunnel is a 50.5 Km from end to end, of which 37.9 Km is underwater. At its lowest point, the Channel Tunnel is 75 metres below sea level.
measured in Km
The longest tunnel in the world used for automobile traffic is the Lærdal Tunnel in Norway. It stretches for 15.23 miles (24.51 km) and connects the cities of Lærdal and Aurland.
If you mean kilometres, the answer is distance.