San Blas is a small fishing and surfing town on the Pacific coast of Nayarit state, about 70 km north of Puerto Vallarta. It has a slow, colonial-era character and sees far fewer tourists than the resorts to the south. The town was an important colonial port — Fort Basilio on the hill above the river mouth is a romantic ruin, and Henry Wadsworth Longfellow set his poem The Bells of San Blas here.
The coast around San Blas is wild and rewarding: excellent surf breaks at Matanchen Bay, estuaries and mangrove lagoons full of birds — this is one of the best birding sites in Mexico, with over 500 species recorded in the area. The boat trip to La Tovara, a freshwater spring reached through mangrove channels teeming with herons and crocodiles, is the classic excursion. The local dish, pescado zarandeado, is one of the best things to eat on the Pacific coast. The famous no-see-um gnats (jejenes) can be ferocious, particularly in the evenings — bring repellent.