To taste the true flavor of this ancient port city, one should stroll its seaside promenade, pausing to rest beneath the huge banyan trees. The narrow, winding streets of the old town fan out from the port, leading you to sunny, palm-lined plazas. Visit the Catedral Nueva (New Cathedral), begun in the early 1800s but not completed for 116 years. Its dramatic, golden dome rises over a striking i…