Puerto Rico.

The surviving San Juan Gate cuts through the old walls to the bayfront path. The harbor facing opening remains one of the most direct ways to understand the city’s historic waterfront defenses.

Passing through the gate shows how visitors once entered the walled city from the harbor. Pair it with the adjacent waterfront walk for context. From the water side, the thickness of the walls becomes much more apparent than it does from inland streets. The passage also creates a satisfying transition between the sheltered old city and the exposed bayfront promenade.

• Harbor-facing gate through city walls.

Use the marked public path along the walls; the gate is an outdoor stop.