"Tunnel Entrance".

A tunnel entrance refers to the opening or entrance of a tunnel, which is a passage or underground structure that allows for the transportation of people, vehicles, or goods from one point to another, often through obstacles such as mountains, hills, or bodies of water.

The design of a tunnel entrance also takes into consideration factors such as geology, drainage, ventilation, and safety requirements. It may include features like lighting, signage, barriers, and monitoring systems to ensure the safe operation of the tunnel.

Tunnel entrances can be fascinating architectural elements, especially in urban areas where they can be creatively integrated into the surrounding landscape or designed to be aesthetically pleasing. Some notable examples of tunnel entrances include the Mont Blanc Tunnel entrance in the Alps, the Channel Tunnel entrance connecting England and France, or the Lincoln Tunnel entrance in New York City.

Overall, tunnel entrances serve as gateways to the underground world, enabling the passage of people and goods through otherwise impassable obstacles and contributing to efficient transportation networks and infrastructure.