Current and historic US Highway ends
in Detroit MI

Research credits: Chris Bessert. Photo credits: Mike Wiley

Let's begin by heading east on Michigan Avenue. Just past the 3rd Street intersection is the last eastbound US 12 marker:

Google Maps Street View, 2008

About three blocks ahead, we come to Cass Avenue, which is the current east end of US 12:

Google Maps Street View, 2008

In another three blocks is Griswold Street, where US 12 ended from about 2000 to 2005:

Google Maps Street View, 2008

In one more block, we come to the end of Michigan at Woodward Avenue...

Google Maps Street View, 2008

...however, that landscaped area wasn't always there - you used to be able to continue straight ahead:

Wiley, 2000

The street ahead is called Cadillac Square. This intersection forms what I would consider "ground zero" of central Detroit's "Grand Circus" street pattern: one of the most aesthetic road plans I've seen. If you center a protractor on this intersection and align the base with the Detroit River (which forms the international boundary with Canada), you'll notice several boulevards radiating outward at approximately 30° increments along a 180° arc, serving all parts of the city and state:

Automobile Blue Book, c. 1929

Woodward is one of these "radials" or "spokes" - it once served as US 10. Michigan Av is another one; US 112 travelers used it. Grand River Avenue (which was US 12 and US 16) is another spoke, and it intersects Woodward two blocks to the left. At various times, all four US routes ended at this intersection, which was where they met a fifth highway: US 25. The photo below is looking north on Woodward:

Google Maps Street View, 2008

US 25 followed what later became M-3: it came in on Fort Street (one block behind the camera), then to this intersection, then right (through what's now the landscaped area) on Cadillac Sq. In a couple blocks, it turned left on Randolph Street, and then northeast on Gratiot Avenue (another spoke). Straight ahead on Woodward was the beginning of US 10, US 12, and US 16. To the left on Michigan was the beginning of US 112 (and later US 12). Below is a photo from that era:

That was taken in Detroit during the "golden age" of US roads. (Since there's no US 10 marker, my guess would be that it was looking west on Michigan Av, somewhere between Woodward and Cass.) Things sure have changed since the 1950s: Michigan has been a "leader" in the movement to decommission US routes, and US 12 is the only one that still serves downtown Detroit. Of course the radial avenues are still there, but today most traffic uses the newer network of freeways - which obscures the grand design of the underlying street pattern.

In the late 1950s, the US 12 designation was removed from the Plymouth Road - Grand River Ave route, and changed to follow the Willow Run - Detroit Industrial - Edsel Ford - John C. Lodge freeways. At that time, it would've ended where the Lodge Freeway ends: on Jefferson at Woodward (which was US 10, so the two routes shared a common terminus). The photo below is looking south on Woodward at Jefferson:

Wiley, 2000

The cars are at what was then the east end of US 10, while the east beginning of US 12 was to the right. That arrangement didn't last long though: it was 1961 when US 112 was decommissioned, and US 12 was changed again - this time to follow the route of what had been US 112. Downtown, that would've put US 12 back on Michigan Av, so the east end would've been back at the old Cadillac Square terminus again (you've already seen a photo from there, above). But then - sometime in the 1970s, perhaps when US 10 was rerouted to use the Lodge Frwy - US 12 traffic was directed south onto Woodward for another three blocks. The designation then ended at the intersection of Woodward and Jefferson again, but this time things were reversed: the cars shown above were at the east end of US 12, and to the right was the east beginning of US 10.

When Mike took that photo, he reported that there was no "End US 12" sign at Jefferson, and there wasn't any signage to indicate that US 12 was routed down Woodward at all. That was right about the time when the state turned over to the city about four blocks of US 12. Heading the opposite direction (westbound on US 12), the first reassurance marker was posted on Michigan at Griswold, which is a block past Woodward:

Wiley, 2000

That's where state highway maintenance began at the time. But in 2005, the state gave up the next three blocks ahead from there - currently the east terminus of US 12 is on Michigan at Cass. Today the first westbound marker is just past 1st Street, which is the next intersection past Cass.

From here, US 12 follows what used to be the route of US 112 through Michigan. The original US 12 was along Grand River Av and Plymouth Road (formerly M-14) out of Detroit to Ann Arbor; and from there through Jackson, Battle Creek, Kalamazoo, and St. Joseph; and then south along the shore of Lake Michigan. After that highway was rendered obsolete by I-94, MI removed much of it from the state highway system, and re-assigned the US 12 designation to the highway that was originally US 112: from Detroit to New Buffalo, via Ypsilanti, Coldwater, and Niles.