Day of the Cacera Mayor (main irrigation channel) Activity · San Cristóbal de Segovia, Alfoz de Segovia, Segovia Image of San Cristóbal de Segovia, not of the place itself. On the last Saturday of May the locals celebrate the Día de la Cacera Mayor, devoted to the cleaning and the recognition of the medieval system of channels that distributes the water of the Cambrones and that sustained agriculture at the foot of the sierra. Photo: Arturo Francisco Barbero (CC BY-SA 4.0) What to see and do in San Cristóbal de Segovia