On my way from Yellowstone to the Black Hills and Badlands I visited Devils Tower Nation Monument (October 2002). Devils Tower is in Eastern Wyoming 27 miles northwest of Sundance via US Route 14.
In 1906 President Theodore Roosevelt made Devils Tower the first National Mounument. Approximately 60 million years ago molten magma was forced into sedimentary rocks and cooled underground. As it cooled it contract and fractured in to the columsn visible today. Erosion of the sourounding sedimentary rock, over millions of years, exposed Devils Tower. The Tower rises 867 feet from its base and 5,112 feet above sea level. The top of the tower is 1.5 acres.
Apon arriving at Devils Tower National Mounument you pass a large praire dog "town." I walked two of the trails. The Tower Trail winds along the base of the tower for 2 kilometers. The Red Beds trail is about 5 kilometers winding between the surounding forest and overs great views of the tower and the surounding area. The photos on this page are from the Red Beds Trail.