6 bridges with vertical clearance data on SR-121 in Michigan. Lowest: 1000.0ft.
| Clearance | Carries | Crosses | Location | Built | Map |
|---|---|---|---|---|---|
| 1000.0ft | M-121 Eb | Macatawa River | 7.5 Mi Ne Of Us-31 | 1955 | Map |
| 1000.0ft | M-121 Wb | Macatawa River | Zeeland Twp Sec 10 | 2004 | Map |
| 1000.0ft | M-121 | Rush Creek | 4.9 Mi Sw Of Kent Co Line | 1949 | Map |
| 1000.0ft | M-121 Eb | Rush Creek | 3.7 Mi Sw Of Kent Co Line | 1941 | Map |
| 1000.0ft | M-121 Wb | Rush Creek | 3.7 Mi Sw Of Kent Co Line | 1972 | Map |
| 1000.0ft | M-121 | Rush Creek | 0.2 Mi Sw Of Kent Co Line | 1933 | Map |