It's a township on the northern edge of the Greater Metro Detroit area.
Washington is just north of Detoilet.
I grew up in Michigan and had not heard of Washington, MI either. It is off of M-53 south of Romeo in Macomb County.
Interestingly, there is a Shelby just south of Washington. This makes two places called Shelby in the state; I grew up near the other Shelby, which is in Oceana County halfway between Muskegon and Ludington (my home town is Fremont, the Baby Food Capital of the World).
Same here.. I had to look it up. But it’s east of Lowell, so it’s Detroit.