The Waltmire Bridge is a historic bridge which carried Locust Road across the Mackinaw River 4.9 miles (7.9 km) south of Tremont, Illinois. The bridge was built in 1910 by contractor Edward Cooney at the site of Waltmire's Ford, a shallow point in the river that could only be easily crossed when water levels were low. Both the ford and the bridge were named for local farmer John Waltmire.