The Ridge Route on US 99 between Castaic and Gorman was a very twisty roadway when it first opened. All told, there was about 39,600 degrees of curvature over the approximately 30-mile route, enough to go in 110 circles. The state gradually worked to alleviate this headache by straightening curves whenever possible. Some curves were merely daylighted where others were completely bypassed. In the case of the Callahan Line Change, as shown in the postcard above, the road was shifted to change eight sharp curves into one gentle curve. The work here was completed in 1926. In 1933, the roadway would by bypassed altogether by the Ridge Route Alternate.