Twenty years ago the region now included in the Province of British Columbia was—with the exception of the coast-line— little known geographically, and quite unknown geologically. From the days of Cook and Vancouver, and the old territorial disputes with the Spaniards, this part of the west coast of North America attracted little attention till the discovery of gold in 1858. As among the first in the field geologically may be mentioned Dr. Hector and Messrs. H. Bauerman and G. Gibbs. The observations of these gentlemen, though bringing to light many facts of interest, were confined to a comparatively small part of the area of the province, and it was not till the inclusion of British Columbia in the Dominion of Canada in 1871 that the systematic operations of the Geological Survey of Canada were extended to this region. Since this date a number of reports treating of the geology of British Columbia have been published, and on these, together with a personal knowledge of the country, obtained during five seasons' work in it in connexion with the Survey, I shall chiefly depend in giving a brief account of the main geological features so far developed.