Crazy!
From 1936 until 1964, U.S. Highway 6 was the longest coast-to-coast highway across America. So, this is an actual sign in California. George R. Stewart, author of U.S. 40: Cross Section of the United States of America, initially considered doing a book on US 6, but realized that "Route 6 runs uncertainly from nowhere to nowhere, scarcely to be followed from one end to the other, except by some devoted eccentric."