The small Iglesia de la Marinera stands within the ruins of Fort Basilio (La Contaduría) on the hill above the river mouth. The church dates from the 18th century, when San Blas was a major Pacific naval base and departure point for Spanish expeditions to California. Its bells inspired Henry Wadsworth Longfellow's final poem, "The Bells of San Blas" (1882), a meditation on faith and the passing of colonial glory.
The church is a ruin now — roofless, its stone walls draped in tropical vegetation — but its setting is extraordinary. From the hilltop you look out over the river mouth, the Pacific, the mangrove estuary, and the red-tiled roofs of the town. The climb from the road below takes about ten minutes on a steep path. Go in the morning or late afternoon; the midday heat on the unshaded hill is fierce.