Wadhams Oil Co. Filling Station
430 S. Second St.
(shown in its original location at 104 W. Walker St.)
1930

Designed by Alexander Eschweiler, these pagoda style stations were very distinctive. This one was originally called the "Clinton Street Filling Station". The first was at 5th & Wisconsin Ave.
This one was moved in 2002 and reincarnated as a coffeehouse. Here's how it looked decades ago.

Only a handful remain:
76th & Ryan Rd. (reportedly being relocated), west of 4th and North Ave.,
76th & National Ave., old and new, and Cedarburg, WI