The Mississinawa River is a tributary of the Wabash River located in west-central Ohio, USA. It flows through several counties, including Darke and Miami, and is approximately 50 miles long. The river is known for its scenic beauty and provides habitats for various wildlife species. The river's watershed is part of the larger Wabash River Basin, which plays a crucial role in the local ecosystem. The Mississinawa Reservoir, created by a dam on the river, is used for flood control, recreation, and water supply, benefiting the surrounding communities.