The earliest mention of Jewish shopkeepers in Aguilar de Campó, situated along the trading route toward the port of Cantabria, is from 1188.

A Hebrew inscription can still be seen under the town’s coat of arms on the old door of the Reinosa . It tells that on 1 June 1380 work on building the door began, paid for by Don Caq (Isaac) ben Malak and his wife Bellida.

The text is in Hebrew and Castilian, with Hebrew characters (aljamiado).