The cones are in the lee of the Lillooet Icecap and sit astride a group of passes between the Bridge River, which flows W-E to their south, and the Lord River, which flows north to the Taseko Lakes in the Chilcotin District.

The Bridge River Cones consist of small trachybasaltic and basaltic eruptive centers.

Sham Hill (50°54′N 123°31′W / 50.90°N 123.51°W / 50.90; -123.51), a 60 m (197 ft) high steep-sided volcanic plug, is the oldest volcano in the field with a potassium-argon date of one million years.

[1] The plug is approximately 300 m (984 ft) wide and its bare glaciated surface, strewn with glacial erratics, consists of large subhorizontal columns formed within the central conduit of an eroded stratovolcano.

[1] Tuber Hill (50°56′N 123°26′W / 50.93°N 123.44°W / 50.93; -123.44), a small basaltic stratovolcano with a potassium-argon date of 0.6 million years, was constructed on the Bridge River upland when neighboring valleys were filled by ice.