The first proper town you’ll come to on a drive south of Donegal Town is this busy, pretty little town, built on a hill, with a 15th-century town center. Some claim (rather dubiously) that Ballyshannon is the oldest town in Ireland, in part because traces have been found of permanent settlements dating as far back as 4000 b.c. Ballyshannon is also the location of Abbey Mills (071/985-1260), a heritage center and craft store. Part of a ruined Cistercian abbey, the mill still has a working waterwheel. (Opening hours vary—generally Monday to Saturday, 10am to 5pm, summer months only; entry is free, but leave a few coins in the collection box by the waterwheel, to help pay for its upkeep.) While you’re here, check out tiny Catsby Cave, about 50m (164 ft.) along the riverbank. During the years of British occupation, when Catholicism was outlawed (from the 16th until the mid-19th century), priests would give Mass here in secret. You can still see the remains of an altar, chiseled from the rock. Admission is free. Ballyshannon is known for its lively pubs, many of which have reliably good traditional music—never more so than during a weekend in late July or early August, when the streets come alive for the Ballyshannon Folk Festival (