The Ice Ages

This exhibit and the Cree Crossing sign about 35 miles west disagree about the Missouri. Here the river is pushed south by ice that arrived about 190,000 years ago; there an ice dam diverts it about 15,000 years ago. Later work leans toward the younger date. In 2006 geologists dating ice-rafted boulders by cosmogenic exposure placed Glacial Lake Musselshell between about 20,000 and 11,500 years ago, not in the Illinoian as long assumed, and concluded that the Missouri's present channel through the Larb Hills may be as young as 11,500 years.

Where it stands

More markers nearby

• Liquid Gold — steps away
• The Old Milk River Bridge and Tampico — 4.6 mi
• Buffalo Country — 7.4 mi