AROW Street
AROW Street is a tunnel in Gibraltar that was excavated in 1942. The tunnel, like Gibraltar's Great North Road, was large enough to take Army ammunition trucks.
Tunnel data from Wikidata (CC0). Summary from Wikipedia (CC BY-SA).
Other tunnels in United Kingdom
Delaware Aqueduct United States · 137 km Päijänne Water Tunnel Finland · 120 km Orange–Fish River Tunnel South Africa · 82.8 km Ishikawa Tunnel Japan · 78.5 km Brenner Base Tunnel Austria · 64 km Mont d'Ambin base tunnel France · 57.5 km Gotthard Base Tunnel Switzerland · 57.09 km Hong Kong–Zhuhai–Macau Bridge China · 55 km