Detroit probably has the least congestion of any of America's ten or so largest metros.
Interesting that this 1947 proposed map isn't too far off from the freeway system that exists in L.A. today. Of course a lot of the names are different...Sepulveda became the San Diego (405), Riverside became the Ventura, San Fernando became the Golden State (5), etc. Leave it to L.A. to become one of the few cities that built, and bettered most of their proposals, and even some that were not proposed such as the Century. That freeway went in on this map just south of the proposed Inglewood Parkway.
I am also wondering if these so-called "Parkways" were proposed as surface streets, or controlled access.