The Beheading of San Juan at Villalmóndar Activity · Valle de Oca, Montes de Oca, Burgos Image of Valle de Oca, not of the place itself. On 29 August the hamlet of Villalmóndar, with eight registered residents, celebrates the Beheading of San Juan, one of the festivals that keep alive the calendar of the six localities of the valley alongside the Nativity of Cueva Cardiel. Photo: WikiBurgos (CC BY 3.0) What to see and do in Valle de Oca