The heavily glaciated faces of the Tantalus Range are prominent from the Whistler Highway (Highway 99) as one drives north of Squamish. The mountains are very rugged, and draped with glaciers. Climbs usually involve a steep and bushy climb from almost sea level, and then either steep glacier work or a rock climb to get to the summit. The solid granite and the proximity to Vancouver makes the peaks particularily attractive for rock climbing. There are several approaches to the area, the most common being across Squamish River via canoe to Lake Lovely Water Trail or by 2WD road to the Sigurd Trail further north. Aircraft are chartered by fly-in parties to Lake Lovely Water.

The range is largely intrusive rock composed of quartz diorite and granodiorite of the Cenozoic-Mesozoic Coast Plutonic Complex. An area of high mineralization potential exists on the western edge of the range, and outside of the park. The mineralization arises from a slender, elongate, NW-trending pendant of metavolcanic and metasedimentary rocks (conglomerate, greywacke, siltstone, argillite, rhyolite) which extends from W of Lake Lovely Water near Red Tusk to the Ashlu shear zone near Falk Creek and is more bulbous near its end points, tapering in the middle, W of Ossa Mountain. Ossa Mountain and Pelion Mountain are part of a large lobe of diorite and gabbro which butts up against the pendant. SW of Fries Creek, Mounts Conybeare, Murchison and Sedgwick are predominately diorite, gabbro and diabase, while SE of Murchison is leucogranite with a small outcrop of pyroclastics near the mouth of the Squamish River at Touch-and-Go Towers.