Union River Bay is a coastal area located in Hancock County, Maine. It is known for its scenic beauty, featuring a mix of saltwater and freshwater environments. The bay is part of the larger Union River estuary, which supports diverse wildlife and offers recreational opportunities such as boating and fishing. The surrounding region includes several small towns, with Ellsworth being the largest nearby city. The bay is also significant for its historical importance, as it has been a site for maritime activities for centuries. Its natural resources contribute to both local economies and conservation efforts.