Mercedes-Benz Museum
Mercedesstraße 137
Stuttgart-Untertürkheim.
49 711 17 2 25 78
Admission: Free

Different models are built at different facilities (Alabama anyone?)
so you check not only where you'll be, but also check when the English speaking tour will be if your Deutch is nicht so gudt.

A Class in Rastatt
SL, SLK, CLK or the C-class in Bremen
C, E, S and CL Class ranges in Sindelfingen