Cuillin range. Cracks and fissures in the rock provided pathways for later magma intrusions, leading to dykes of basalt which are commonly seen across Skye. The Red Cuillin also have volcanic origins, being formed from a later intrusion of acidic, granitic rock. This granite was more uniformly eroded by wind and water than the gabbro and basalt, causing the red hills to have smoother outlines. The Cuillin provide classic examples of glacial topography and were the subject of an early published account by James Forbes in 1846 (who had become a fellow of the Royal Society of Edinburgh aged only nineteen).
Hills in the Puget Lowland counties) Whidbey Island and Camano Island are islands in Puget Sound and form the bulk of Island County. The Blue Hills of the Kitsap Peninsula are unusual in that they are composed of basalt bedrock, not glacial till. Bainbridge Island is an island in Puget Sound. Landforms in South Puget Sound (Thurston and Mason counties) The Issaquah Alps Bellevue, Issaquah and Newcastle on the Eastside are considered part of the Cascades foothills by many authors. They are basalt intrusions possibly related to the Blue Hills of the Kitsap Peninsula. Highest point Tiger Mountain summit, . The Anacortes Community Forest Lands