The Ice Age Trail began with the idea of an Ice Age Glacier National Forest Park to be established along the entire length of the moraines marking the edge of the last glacier in Wisconsin. This original concept eventually led to the creation of the nine unit Ice Age National Scientific Reserve through Federal legislation in 1964 and 1970. The reserve units, administered by the Wisconsin Department of Natural Resources, were created to protect, preserve, and interpret the outstanding examples of glaciation in Wisconsin.

Though work on the trail itself was begun by volunteers in the 1950's, it was not designated a National Scenic Trail until 1980. Today, the Ice Age Trail links together six of the nine units of the reserve.

Detailed information about the geology of the Scientific Reserve Units can be found in "Geology of Ice Age National Scientific Reserve" of Wisconsin" by Robert F. Black. Please note that the names of some of the units referred to in the book have changed in the years since it was originally published.

The Nine Units are:

Two Creeks Buried Forest *
Kettle Moraine *
Campbellsport Drumlins
Horicon Marsh
Cross Plains * (Cross Plains Feasibility Study)Devil's Lake *
Mill Bluff
Chippewa Moraine *
Interstate State Park *

(* along the route of the Ice Age Trail)