OPW Heritage Ireland places in County Louth

The Red Earl's Dominican friary of 1305 at the edge of Carlingford, a fortified church with a central tower, crenellated west gable and murder hole, later a barracks and handball alley; free, open-air, limited parking nearby.

A ninth-century round tower, the east gable of a medieval church and the carved head of a tenth-century high cross in the graveyard of Dromiskin village, between Dundalk and Castlebellingham; free, open-air.

Ireland's first Cistercian abbey, founded in 1142 near Drogheda, with a two-storey octagonal lavabo; grounds free, the visitor centre and tours (€5) closed until the 2027 season.

A three-storey tower house with a corbelled stone roof and battlements overlooking the Irish Sea in Termonfeckin village, County Louth; free, with the interior opened by a key borrowed from a neighbouring house.