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| Route information | ||||
|---|---|---|---|---|
| Maintained by ODOT | ||||
| Length | 39.02 mi (62.80 km) | |||
| Existed | 1924–present | |||
| Major junctions | ||||
| South end | ||||
| North end | ||||
| Location | ||||
| Country | United States | |||
| State | Ohio | |||
| Counties | Marion, Crawford, Seneca | |||
| Highway system | ||||
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State Route 100 (SR 100) is a north–south highway in northwestern Ohio. Its southern terminus is at State Route 309 near Iberia, and its northern terminus is at State Route 53 in Tiffin.
Established in 1924, the original routing was from 1-mile (1.6 km) north of Brokensword to Tiffin. In 1939, it was extended to 12 miles (19 km) south of Bucyrus along route 19 from 1-mile (1.6 km) north of Brokensword to 3 miles (4.8 km) south of Bucyrus and an unnumbered road from 3 miles (4.8 km) south of Bucyrus to 12 miles (19 km) south of Bucyrus.
| County | Location | mi | km | Destinations | Notes |
|---|---|---|---|---|---|
| Marion | Iberia | 0.0 | 0.0 | Southern Terminus. | |
| Crawford | Bucyrus | 9.11 | 14.66 | Southern terminus of SR 19 concurrency; SR 19 continues south. | |
| 12.53 | 20.17 | Southern terminus of SR 4/SR 98 concurrency; SR 4/SR 98 continue south. | |||
| 12.67 | 20.39 | Northern terminus of SR 98 concurrency; SR 98 continues north. | |||
| 13.46 | 21.66 | Full-access interchange with US 30. | |||
| 14.02 | 22.56 | Northern terminus of SR 4 concurrency; SR 4 continues north. | |||
| Lykens Township | 21.3 | 34.3 | Northern terminus of SR 19 concurrency; SR 19 continues north. | ||
| 25.12 | 40.43 | Eastern terminus of SR 103 concurrency; SR 103 continues east. | |||
| 25.26 | 40.65 | Western terminus of SR 103 concurrency; SR 103 continues west. | |||
| Seneca | Melmore | 30.57 | 49.20 | Southern terminus of SR 67 concurrency; SR 67 continues south. | |
| 30.83 | 49.62 | Northern terminus of SR 67 concurrency; SR 67 continues north. | |||
| Tiffin | 35.56 | 57.23 | |||
| 37.88 | 60.96 | Southern terminus of SR 231 concurrency; SR 231 continues south. | |||
| 38.23 | 61.53 | Northern terminus of SR 231 concurrency; SR 231 ends. | |||
| 38.29 | 61.62 | ||||
| 39.02 | 62.80 | Northern terminus. | |||
1.000 mi = 1.609 km; 1.000 km = 0.621 mi
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