The cathedral of El Burgo de Osma mingles Gothic (south porch), Late Gothic (cloister) and Renaissance (chancel) influences. Inside, note the fine 16C railings by Juan Francés, the main altarpiece devoted to the life of the Virgin, and the tomb of St Peter of Osma in multi-coloured limestone (13C). In the museum, among the collection of old archives and illuminated manuscripts, keep an eye open for a richly illustrated Beatus dating from 1086.