Located in the furthest southeast part of the state, this unit’s east border is along the boundary line of the state of Iowa and the Big Sioux River. The south border follows along the state of Nebraska and the Missouri river. This unit consists of almost no public land, with the exceptions of Union Grove State Park, and Adam’s Homestead and Nature Preserve. If you plan on coming to this unit, prior arrangements with a private landowner are recommended. Union county makes up the entirety of the unit and is the most south-eastern county in the state. The terrain is a mix of rolling hills, devoted almost entirely to agriculture except around built-up areas.