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.

In this article, we'll explore what makes tunnels such an attractive solution for railways, roadways, public utilities and telecommunications. We'll look at the defining characteristics of tunnels and examine …

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.

6 days ago · 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.

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

Tunnels that transport people by rail or by automobile often comprise two or three large, parallel passages for opposite-direction traffic, service vehicles, and emergency exit routes. The world's …

The following is a list of some tunnels in the United States of America. More tunnels may be found in each state than are included on this list.