Porte Prescott is one of the gateways in the fortified old city, linking the Upper Town and Lower Town. The original gate was built in 1797 and named for Robert Prescott, then governor general of Canada, though the current version is a 1984 reconstruction.
It is a small stop, but useful on a walk through Vieux-Quebec because the stairs beside the gate lead up to the wall. Treat it as part of the old-city route rather than a standalone destination.