Bordering Wales in far-west Gloucestershire (and parts of Herefordshire), between the Severn and Wye rivers, the mysterious Forest of Dean is a 42-square-mile natural wonderland packed with adventure. Find quiet trails through England’s oldest oak forests (whose secluded beauty inspired JK Rowling and JRR Tolkien); kayaking, paddle-boarding, and birdwatching from the riverside village of Symonds Yat; plus caving, rock-climbing, abseiling, and rafting.