The excavation of the castle of Lorca (Murcia) over the last fifteen years has brought to light the archaeological remains of a complete Jewish quarter from the 14th and 15th centuries. Among the different elements found, its synagogue stands out, which is one of the few preserved examples of this type of medieval building that has come down to us without having been transformed into a church, and its spectacular set of glass chandeliers. The project developed in the late medieval Jewish quarter of Lorca allows us to reconstruct daily life on the Castilian-Nazari border and to define some archaeological indicators for the identification of medieval Jewish populations.