Upon arriving in Whistler, even before you begin hiking any of the Whistler trails, your gaze will be pulled skyward. The surrounding mountains are so close, steep and tall, you immediately sense the titanic forces that shaped them: fire and ice (volcanism and glaciation).
A cursory geology lesson proves your instincts were correct. Eons of our planet's history are evident in the mountains walling off Whistler from the rest of the world. While hiking Whistler trails, ponder these three geologic phases:
(1) The B.C. Coast Range is primarily granitic rock that collided with North America about 100 million years ago.
(2) As the Juan de Fuca plate inexorably moves beneath the western edge of the continent along the Cascadia subduction zone, partial melting of rocks deep in the earth's crust feeds volcanoes that have broken through the ancient bedrock. The prominent local example is Mt. Garibaldi, now dormant.
(3) When the last Ice Age climaxed 17,000 years ago, most of British Columbia including present-day Whistler was covered by an ice sheet 2 km (1.2 mi) thick. Only the highest peaks in the range protruded above. Along the coast, glaciers eroded fiords, Howe Sound for example, similar to those of Norway. Remnants of those great glaciers still cling to many of the loftiest mountaintops, adding to the scenic wattage of Whistler trails.
Go to http://www.hikingcamping.com/photos-whistler.php to see photos from the premier Whistler trails.
Go to http://www.hikingcamping.com/hike-whistler.php to read about Done in a Day Whistler, The Ten Premier Hikes. That's the book you'll want if you're keen to hike Whistler trails.