From 348 residents to 35 Historical milestone · Castilfrío de la Sierra, Almarza, Soria That year's census counted eighty-five households and 348 inhabitants in the village, and in the mid-nineteenth century some hundred houses were attributed to it; today the register records thirty-five people. 1842 Photo: Diego Delso (CC BY-SA 4.0) What to see and do in Castilfrío de la Sierra