The bull runs (encierros) documented since 1215 Activity · Cuéllar, Tierra de Pinares, Segovia Image of Cuéllar, not of the place itself. The first known mention of the encierros of Cuéllar is from 1215, in a prohibition addressed to the clergy so that they would not take part in them; that document makes them the oldest documented encierros in Spain. 1215 Photo: Rowanwindwhistler (CC BY-SA 3.0) What to see and do in Cuéllar