Festivities of invierno de Tosos Activity · Tosos, Campo de Cariñena, Zaragoza Image of Tosos, not of the place itself. Tosos's winter festival is held in a village on the banks of the Huerva whose main festival, in honour of San Bartolomé, runs for four or five days from 24 August; the castillo de la Casaza served in the Middle Ages as one of the two signal watchtowers of the district. Photo: 19Tarrestnom65 (CC BY-SA 4.0) What to see and do in Tosos