It flows into the Mississippi River about 3 mi (5 km) southwest of Dickeyville, across from Mud Lake, Iowa.

Many steep limestone bluffs dominate the landscape, often covered by white pine, which is uncharacteristic in the region.

[6] The combination of the rugged terrain and extensive agriculture leads to significant runoff after storms, contributing to the many rapids along both rivers.

[3] Local fishing is also popular, with the most common species being smallmouth bass, channel catfish, and northern pike.

DNR staff believe runoff from barnyards and feedlots, particularly in some headwaters areas, to be a severe problem in this watershed.

"[9] According to a 2001 report, the main environmental issues are nonpoint source pollution in the forms of agricultural and urban runoff; soil erosion; mine waste; and a decline in the smallmouth bass population.

The Friends of the Platte River, Inc. bills itself as a "group that exists to serve as a forum to address issues affecting the Platte/Little Platte River watershed and to seek impartial solutions that restore, enhance, and protect this valuable resource."