When the Pony Express delivered mail in 1860, they probably didn't follow a police motorcade or carry GPS in their saddlebags.

But that was what happened on Penn Street Saturday as 10 horses galloped into town on the last leg of the annual Pony Express Rerun, a 10-day trek across eight states involving 550 riders. The majority of the riders were from Kansas or Missouri, but one Wyoming resident was among their ranks after riding nearly 2,000 miles from the run's starting point in Sacramento, Calif.

Most participants only rode through their home states, said Les Bennington, president of the National Pony Express Association.

Participants rode 24 hours a day.

"You can't just do daylight rides, you'll never make it - not in 10 days, anyway," Mr. Bennington said after stepping off his horse for the last time in boots, fringed leather chaps and a cowboy hat.

Mr. Bennington is very much aware of the historical significance of the rerun.

"One of the most interesting things to me is that (the Pony Express) was an endeavor against man and a horse race against time," he said.

For the first time in the ride's history, GPS was placed in the leather mochila used to haul 1,100 commemorative letters across the country. The system allowed followers to track the progress of the ride online.

"Even though the Pony Express is 148 years old, we're still using modern technology, but we're still carrying the mail by horse," said Gary Chilcote, Patee House Museum director.

The rerun, which is nearly 30 years old, can be a big undertaking but is worthwhile in the end.

"We try to keep the story of the Pony Express alive and commemorate it," Mr. Chilcote said.

For the riders, it's a chance to relive history. Amy Beaty, who rode the last leg in from Elwood, Kan., said the best part is riding over the bridge that crosses the Missouri River.

"When you drive a car you don't see what you see on horseback," Ms. Beaty said.