The Sidlaws (Scottish Gaelic: Na Sidhbheanntan [1], also called the Sidlaw Hills and Sidlaw Range, are a range of hills of volcanic origin in the counties of Perthshire and Angus in Scotland that extend for 30 miles (45 km) from Kinnoull Hill, near Perth, northeast to Forfar. Principal peaks within the Sidlaws include Ark Hill and King's Seat.