Commissioned before A.D. 1230, Dolbadarn Castle in Snowdonia National Park features the best surviving example of a Welsh round tower.
Take a walk on the moors, go horseback riding on ancient trails, or tour a medieval village in one of the U.K.'s 15 national parks. Known as "Britain's breathing spaces," the parks offer outdoor and sightseeing activities against dramatic landscapes and historic treasures. Discover the parks in our profiles and gallery—and plan your next trip.
Photograph by Alan Novelli, Alamy