The Pony Express held a technological shelf life in the early 1860s for about as long as an unpopular smart phone nowadays.

But from April 3, 1860, to Oct. 21, 1861, it stood as a transportation marvel for moving mail -- $5 for a letter -- 2,000 miles in about 10 days through now eight states from St. Joseph, Mo., to Sacramento, Calif.

And the Central Wyoming Chapter of the National Pony Express Association doesn't want you to forget that.

"We're mostly trying to keep history alive by going across the United States on the eight states," chapter president Jay Jensen said.

This year's re-enactment left St. Joseph at 10 a.m. Monday, arrived early in Casper on Friday, and probably will conclude Thursday.

At 9 a.m., Jensen urged his horse uphill from to the National Historic Trails Interpretive Center during the annual re-ride of the Pony Express.

Jensen and his steed trotted to the log cabin at the center where he dismounted and others with the association unhitched the mochilla -- leather mail bag -- from the horse and hung it over the saddle of another horse.

A new rider mounted the new horse and rode a few miles to Fort Caspar, which was one of more than 180 stations along the original route, which included 42 in Wyoming.

The Pony Express company fixed Wyoming as a major frontier territory, gained fame with riders including Buffalo Bill Cody, and delivered the mail despite the hazards of weather and terrain. It would live on through movies, television and books.

But it couldn't live in its own time with a money losing proposition, and the rolling tide of new technology.

"And the telegraph came in and put them out," Jensen said.