Virtual Tour of the Ridge Route

Virtual Tour of the Ridge Route


One of the first roads to be constructed under the Highway Bonds was the “Castaic-Tejon Ridge Road”, known today as the “Ridge Route”. Hailed as a marvel of engineering in its time, it would last as the main road from Los Angeles to Bakersfield for 18 years. The roadway exists today in segments and is in part federally protected on the National Register of Historic Places. The Ridge Route was the first major highway project and first new mountain road project undertaken by the State.

Surveys began for the Ridge Route in 1912, mostly following a ridge line which ran from Castaic to Gorman. Construction commenced shortly after. Using mostly manual labor, consisting of picks, shovels, and Fresno scrapers, the highway was opened in November 1915. At first, the highway was only oiled and graded. Starting in 1917, the highway was paved with a 20′ wide slab of reinforced concrete. Paving was completed by early 1920.

As there was only a finite amount of money for the project, this route was used to keep costs down. Following the ridge kept costs down as no bridges were needed. Keeping costs down did have its problems though. The maximum grade allowed on the Ridge Route was 6%. To keep this gradient, many curves were added to the roadway. So many curves had to be used, in fact, that the total curvature added to over 110 complete circles in the 30 mile stretch. This fact would quickly make the highway a very dangerous and slow one. Collisions became commonplace. A speed limit of 15 mph was put into place along the entire road from Castaic to Gorman as a result of this.

Speed limit sign posted near Castaic.

Many sections of the road needed to be realigned for safety. Many of the cuts were “daylighted”, a process in which the hillside is cut back to increase visibility. In other places, the roadway was widened where it was possible. These realigned sections were paved with an early version of asphalt paving. Much of these early paving surfaces are still around today. By the late 1920’s, it was evident that this work was only a temporary measure. A new route had to be found. This option was both more economical and less disrupting to traffic. The new route, called the Ridge Route Alternate, was finally opened on October 29, 1933, completely bypassing the old Ridge Route. This bypass forever relegated the old road to a scenic side road traveled by few. On September 25, 1997, the Ridge Route from just north of Templin Highway to Sandberg, within the Angeles National Forest, was granted historic status on the National Register of Historic Places. This designation has helped with the preservation and restoration of this historic roadway,

A rare smooth section of concrete, near the Halfway Inn.

Currently, I have only a few historical photos of the Ridge Route. I am working on getting some but if you happen to have any, please let me know.

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