While outlaws roamed the windswept high plains, canyons and mountains of post Civil War Wyoming, the territorial legislature was planning a state-of-the-art penitentiary at Rawlins in anticipation of statehood. This new Wyoming State Penitentiary, which would serve from 1901 until 1981 would send a strong message to freewheeling desperadoes... Wyoming would no longer be a haven for the lawless. The Old Pen, as the Wyoming Frontier Prison is affectionately called today, is “haunted by history” around every corner. Tales of great train robbers, wily escapes and of women driven to crimes of passion are told on the scheduled guided tours offered from April through October. Group tours and off-season tours are also available.

The Pony Express National Historic Trail was used by young men on fast paced horses to carry the nation's mail across the country, from St. Joseph, Missouri to Sacramento, California, in the unprecedented time of only ten days. Organized by private entrepreneurs, the horse-and-rider relay system became the nation's most direct and practical means of east-west communications before the telegraph. Though only in operation for 18 months, between April 1860 and October 1861, the trail proved the feasibility of a central overland transportation route, and played a vital role in aligning California with the Union in the years just before the Civil War. Most of the original trail has been obliterated either by time or human activities. Along many segments, the trail's actual route and exact length are matters of conjecture. However, approximately 120 historic sites may eventually be available to the public, including 50 existing Pony Express stations or station ruins.

South of Riverton, Wyoming, the Mormon Handcart Companies has a Visitor's Center at Martin's Cove. You can get handcarts to trek into the cove both summer and winter.

The Grand Encampment Museum, located in Encampment, Wyoming, preserves history with its collection of over a dozen historical buildings filled with artifacts representing the timber, mining, and agricultural history of the Encampment valley.

This unique historic place preserves and interprets one of America's most important locations in the history of westward expansion and Indian resistance. Established in 1834, Fort Laramie began as a fur trading post. By the 1840s, wagon trains rested and resupplied here, bound for Oregon, California and Utah. In 1849 as the Gold Rush of California drew more westward, Fort Laramie became a military post, and in 1876, Fort Laramie served as an anchor for military operations, communication, supply and logistics during the "Great Sioux War." Fort Laramie closed in 1890.