It is dug through surrounding soil, earth or rock, or laid under water, and is usually completely enclosed except for the two portals common at each end, though there may be access and ventilation …

tunnels and underground excavations, horizontal underground passageway produced by excavation or occasionally by nature’s action in dissolving a soluble rock, such as limestone. A vertical opening is …

The meaning of TUNNEL is a covered passageway; specifically : a horizontal passageway through or under an obstruction. How to use tunnel in a sentence.

Constructing a tunnel is one of the most complex challenges in the field of civil engineering. Learn about the basics behind tunnels.

Dec 4, 2025 · Explore the world’s 10 longest tunnels, record-breaking engineering marvels that push the limits of design, scale, and human ambition.

TUNNEL definition: 1. a long passage under or through the ground, especially one made by people: 2. the long passage…. Learn more.

In general, tunnels are at least twice as long as they are wide and are completely enclosed on all sides, save for the openings at each end. A tunnel may be used by pedestrians, cyclists, motor vehicles, or …

Dec 2, 2025 · The world’s longest and deepest undersea road tunnel is being built in Norway, intended to cut travel time between major cities and become part of a ferry-free highway along its western coast.

A tunnel is a long passage which has been made under the ground, usually through a hill or under the sea. Boston drivers love the tunnel.

Tunnel definition: A passage through or under a barrier such as a mountain.