Gwydyr Forest covers some 28 square kilometres of the hillsides around Betws-y-Coed, planted mainly with conifers from the 1920s onwards. It is the most accessible large woodland in Snowdonia, threaded with forest roads, lakes and waymarked walking and mountain-bike trails of every grade.
The Marin Trail is one of the best-known mountain-bike routes in Wales — a 25 km loop with steep climbs and committing descents that draws riders from across the country. Walkers have it easier: the Forestry Commission has signposted routes from short family loops to half-day forest crossings.