The Romanesque monastery church of San Pedro de Siresa, in the small village of Siresa about 3 km north of Hecho, dates in its current form to the eleventh century, though a monastery has stood on this site since at least the ninth. The church is one of the oldest surviving Romanesque buildings in Aragon — solid, austere, and in remarkable condition given its age.
The setting is quiet: a handful of stone houses, a small square, and this old church that has outlasted everything around it. Opening hours are limited; a key is sometimes available from the village. Even if the interior is closed, the exterior is worth the short walk or drive from Hecho.