The tallest of the seven hills that form Holyrood Park at 822 feet (250m), Arthur's Seat is actually an extinct volcano that overlooks the city of Edinburgh. There are the remains of an Iron Age hillfort, with several grassy plateaus that make for pleasant stopping points on the way up. Described by poet Robert Louis Stevenson as "a hill for magnitude, a mountain in virtue of its bold design", Arthur's Seat is popular for hikes, and the view from the top of Edinburgh and the surrounding countryside is well worth the climb. There are many ideas of how the hill got its name, among them the famous legend of King Arthur and his half-sister Morgan Le Fay.