Milk River is on the east side of Milk River Ridge, an area more than 1,200 metres (3,900 ft.) high, 39 kilometres (24 mi.) long and 29 kilometres (18 mi.) wide. Quartzite, granite and gneiss rock formations indicate prehistoric glacial action; meltwater carved the Milk River Valley 10,000 years ago. The river, formed from small streams and springs in southwest Alberta and northern Montana, joins the Missouri and Mississippi rivers to flow to the Gulf of Mexico. Learn More...