Driving down a California highway, you’ll notice the state’s highway signs don’t look like most others. The Golden State’s signs stand apart for their distinctive spade shape, which are nothing like the circles and rectangles used across the rest of most of the country. It’s not random, either. It’s a callback to an important part of the state’s history: The Gold Rush.
First adopted in 1934, the rounded triangular edges of the signs come together in a curved point at the top. It’s supposed to look like a miner’s spade, just like what the Forty-Niners used when they flooded the region in search of gold. The emblem not only points drivers toward their destinations but also hearkens back to the past. Old-timey prospectors carved the state’s most well-trodden paths through incredibly rugged terrain in search of fortune. Present day, those paths now stand as some of California’s busiest transportation routes.
The evolution of California’s highway signs
Over 90 years later and the signs are still in use today. However, that’s not to say the design hasn’t gone through changes since 1934. For example, earlier versions of the sign featured a grizzly bear silhouette — the animal was once native to California but was driven to extinction in the state by 1924. That part of the sign was eventually removed in 1957.
A 1964 update dropped the black backgrounds with white lettering and introduced the current green coloring. This was when they softened the spade’s upper point, as well. Studies showed that these colors had better contrast and could be read from longer distances at night compared to other color combos, such as blue and gold or black and white.
In the late ’90s, state transportation officials introduced retroreflective materials to the signs. This made nighttime visibility even better, improving readability from roughly 400-600 feet to as far as 1,600 feet. The retroreflective materials also let California get away from internally lit signs, which had been vulnerable to copper wire theft which, by the way, is the same reason people steal Tesla charging cables.
