Tunnel

A tunnel is a passageway through or under an obstruction, like a mountain.

The Gotthard Base Tunnel is the world's longest tunnel with 57 kilometers (around 35 miles) through the Swiss Alps, completed after 6 decades of work in 2010,[1] and opened on the first of June 2016, and in full service on 11 December 2016.[2]

Until then the longest tunnel in operation was Japan's Seikan Tunnel.

## Notes[edit]

1. ↑ Joyous Swiss celebrate longest tunnel
2. ↑ https://www.bbc.com/news/world-europe-36423250