Stone, brick and paint are harmoniously combined in this simple church, one of the most unique in all of Aragon, built on the foundations of an earlier mosque.
Work on construction began on the apse of dressed stone, as is common in Romanesque art; but half-way through, Mudejar architects took over the work and abandoned stone for their traditional bare brick, with which they completed the church. It is modest in size, with a single nave, a chapel on each side of the transept (14th century), a presbytery and apse. An atrium forms the main doorway. Inside, the nave is covered with a wooden roof. The apse is decorated with five blind arches, over which there are remains of some of the Gothic mural paintings (14th century) that used to cover it entirely: an image of Saint John can be seen, and above it, an elongated depiction of the Last Supper.