In a well-kempt colonial neighborhood several blocks southwest of the parque central, the Iglesia y Ex-convento San Bernardino de Siena (Calle 41-A, tel. 985/856-2160, 8 a.m.–noon and 5–7 p.m. Tue.–Sat., until noon Sun.) is one of Valladolid’s most attractive structures.

Built by Franciscan missionaries between 1552 and 1560, the church entrance is through a series of arches, and the facade, covered in a checkerboard-like stucco pattern, rises into a squat tower complete with turrets. Annexed to it, the ex-convent has rooms radiating from a center courtyard, which features, uniquely, a cenote.

Called Sis-Há (Cold Water), the cenote helped the monks to be self-reliant. In 2004, an exploration of the cenote resulted in the discovery of 164 rifles and one canon—neither the age nor the nationality of the arms have been disclosed.

Mass is held in the church at 7 p.m. Tuesday to Saturday, and at 7 a.m., 9 a.m., 11 a.m., 6 p.m., and 7 p.m. on Sunday.

Special permission is required to visit the ex-convent; call ahead or ask in the church office.