Fodor's Expert Review Baluarte de Santiago
The small fortress is all that's left of the old city walls. Like the Fuerte de San Juan de Ulúa, the colonial-era bulwark was built as a defense against pirates. The 1635 structure is impressively solid from the outside, with cannons pointed toward long-gone marauders. Inside is a tiny museum that has an exquisite exhibit of pre-Hispanic jewelry—Spanish plunder, no doubt—discovered by a fisherman in the 1970s.