The church dedicated to Sant'Erasmo, who according to tradition died martyred in 303. Close to the church, stands on an ancient early Christian necropolis, of which some structures are preserved in the crypt of the current church. The medieval basilica, which in the eleventh century was part of the possessions of the powerful Benedictine abbey of Montecassino, was destroyed during the Turkish invasion of the first half of the sixteenth century. It was rebuilt at the behest of Emperor Charles V. The church has a longitudinal plan without transept and is preceded by a narthex. Internally it has three naves with a large presbytery and a roof with cross vaults. At the end of the right aisle is the chapel of Sant'Erasmo, with the eighteenth-century altar and the wooden statue of the Saint.
The underground crypt houses an Antiquarium where traces of the early medieval attendance of the site are preserved, including the tomb of the martyr and some early Christian burials, of which fragments of funerary epigraphs are preserved. There are also architectural fragments from the so-called Carolingian Chapel.
