Arco de Santiago, or St. James’s Arch, an integral part of the historical and architectural complex of Plentzia’s old quarter, is of great historical value.

Aesthetically, it has little to recommend it: it is a simple arch between two buildings at the vertex of the plaza. However, it constitutes the only remains of the walls that surrounded the town of Plentzia, erected around 1236, and which with time and the expansion of the urban nucleus have fallen into ruin or disappeared in the walls of other houses.