A fly-infested region of marshland in central Eriador, that lay between the Chetwood to the west and the Weather Hills to the east. Midgewater was a morass of shifting pools that took its name from the swarms of midges that filled the air. In the central regions of the marshes dwelt the Neekerbreekers: night-creatures of cricket-kind.

In an attempt to avoid the East-West Road, Aragorn led Frodo and his companions through the marshes on their journey from Bree. Travelling slowly through the treacherous quagmire, their crossing took two days from the western to the eastern edge.