Founded in 1471 by Calvagh O’Donnell for the Franciscan Third Order Regular, this friary managed to survive relatively intact until its suppression around 1603, when it was granted to Captain Basil Brooke. The complex comprises a church with chancel, nave and south transept, along with domestic buildings arranged around the northern and eastern sides of an open courtyard. Though the transept appears to be a later addition, the domestic ranges were likely built at the same time as the main church structure.

The church itself measures 24 metres by 6.25 metres internally and showcases sophisticated medieval craftsmanship despite its ruined state. The east window, though missing most of its tracery and lower sections, retains enough detail to suggest it originally featured four lights with a cusped quatrefoil at its apex. Throughout the building, architectural elements like ogee-headed windows, sedilia recesses, and wall-presses reveal the careful planning that went into creating this sacred space. The south transept contains two barrel-vaulted altar recesses in its eastern wall, whilst the domestic ranges featured ground floor chambers that were all originally vaulted, with most vaults running east to west.

After falling into disrepair, the friary underwent significant alterations, likely by the Stewart family who converted the sacristy into their family burial vault. This renovation work, which included squaring off walls and repointing faces, makes interpreting the building’s original layout somewhat challenging. Despite these changes, enough structural evidence remains to appreciate the complexity of this religious house; from the segment-headed embrasures at second storey level that still show traces of wicker-centering in their soffits, to the squint that once allowed a view of the high altar from the upper floors. The surviving architectural details, including roughly-coursed rubble blocks with ashlar quoins and various moulded features, offer a fascinating glimpse into the religious life and building practices of 15th-century Donegal.