The Mournes are the obvious draw to Down, and there are some great walks here. They aren’t high mountains; there’s almost no scrambling. But they’re steep and it’s often hard to get into a comfortable rhythm, so you certainly earn the altitude.
They’re compact, so it possible to get a good feel for the place in only two or three days. Be prepared for wet feet; there are some very boggy areas which leave you with no option but just to plough on through (Castle Bog on Eagle Mountain is a classic example of this).
For more gentle walking, there are a number of fabulous beach and coastal walks in south Down. A good guide is ‘25 Walks in Down District’, published by the Stationery Office. This also covers some inland walking on the ancient green lanes between dry stone walls and rolling green hills.
Elsewhere in the county, it can be frustrating for those used to public rights of way and CROW; there isn’t a large network of footpaths through much of what is wonderful countryside, like there would be in England, for example. Country parks (Scrabo, Redburn and Crawfordsburn) allow good walking and viewpoints, however.
Besides walking, Downpatrick has plenty related to Ireland’s patron saint, plus a working steam railway. In Portaferry, the aquarium and seal sanctuary offers hands-on learning about local sealife. Bangor is a fine seaside town if great appeal and, at Cultra, the Ulster Folk and Transport Museum is one of the best in Ireland.