The Tunnel of the Templars is one of Acre's most atmospheric Crusader remains. The stone passage once linked the Templar fortress on the western side of the city with the port, letting knights and supplies move under the crowded streets above.
The tunnel was rediscovered in the 1990s and is now restored with a raised walkway and lighting. It is a short visit, but a good one: cool, enclosed, and easy to pair with the Hospitaller Fortress, old market, and sea walls.