Rollinsville is a census-designated place and a U.S. Post Office located in Gilpin County, Colorado, United States. It is located in the mountains southwest of the city of Boulder, on the flank of a hill above South Boulder Creek along State Highway 119 betweenNederland and Black Hawk. It consists of a small cluster of residences and several businesses at the terminus of the road leading westward up to Rollins Pass at the summit of the Front Range. The population as of the 2010 Census was 181. The Rollinsville Post Office has the ZIP Code 80474.
Rollinsville is located at 39°54′59″N 105°30′03″W (39.916320,-105.500851).
Rollinsville was established by John Q. A. Rollins, a prominent mining executive in Gilpin County in the 1860s and 1870s.
South Fork Boulder Creek flows just south of the town. The creek follows the railroad tracks into a small canyon and emerges near the Boulder/Gilpin county border before flowing through Pinecliffe, Colorado.