Identified as Camp Floyd in the 1861 mail contract, this station had various other names including Fairfield, Fort Crittendon or Crittenden, Carson's Inn, and Cedar City.  The settlement of Fairfield began in Cedar Valley in 1858, when John Carson, John Williams, William Beardshall, John Clegg, and others built homes and a protective enclosure called Cedar City Fort. John Carson built an adobe inn that same year, which served as a station for both Pony Express riders and stage lines. In 1858, General A. S. Johnston and his troops established a fort near Fairfield, which they named in honor of John B. Floyd, Secretary of War.  Troops stayed at the Camp Floyd until early in the Civil War, when they headed east to join the fighting. After Secretary of War Floyd joined the Confederacy, Union officials renamed the Utah garrison Fort Crittenden. 

The adobe station existed as late as 1979, with a wooden facade, under the protection of the Utah Parks system.

http://www.nps.gov/parkhistory/online_books/poex/hrs/hrs7a.htm#109

Camp Floyd/Fairfield Station (N40 15 37.9 W112 05 34.4) (M#82) 

Location: NE1/4NW1/4 Section 32, Township 6 South, Range 2 West, Salt Lake Meridian, 8 ¼ miles from Dugout Station. 

In 1857, President James Buchanan sent an army of U.S. troops under Albert Sidney Johnston to quell a purported uprising in Utah. When the “Mormon War” was settled in 1858 without a battle, Johnston and his army of 3000 Union soldiers built Camp Floyd, named for Secretary of War John B. Floyd. The pastoral village of Fairfield soon became a raucous town of 7000, including 17 saloons, the third largest city in Utah. Then the Civil War broke out and in early summer of 1861, the army, now under Col. Phillip St. George Cooke, was recalled to the United States. John Carson built his two story home in Fairfield in 1855. The Carson Inn, the building now known as the Stagecoach Inn, served as an Inn and a station for the Overland Stage. Today it is the centerpiece of Camp Floyd/Stagecoach Inn State Park. The Pony Express Station was a small adobe building about a block northeast of the Inn. It is still standing, has a wooden facade, and is open to the public as a Utah State Park. It was operated by the family until 1947. Such personages as Horace Greeley, Mark Twain, Sir Richard Burton, Porter Rockwell, Bill Hickman, and General (then Colonel) Albert Johnston stopped at the inn.

For soldiers marooned in this desert spot, knowing that civil war seemed eminent, news from the east was eagerly awaited. On “Pony Day,” the day when the pony express mail was to arrive, a lookout was stationed on the roof of one of the camp buildings to raise a cry when the pony rider came in sight.

In 1858 James Hervey Simpson was a Captain in the Army Corp of Topographical Engineers. When President Buchanan ordered the Army to send troops to Utah to put down “The Mormon Rebellion,” Simpson was attached to the command of Brigadier General Johnston and sent to Camp Floyd. Soon after arriving here he was assigned to make a preliminary reconnaissance into the desert to the west in an effort to find a central route to California. Prior to this time, anyone heading west from Salt Lake City had to go around the north end of the Great Salt Lake and down the Humboldt River, or follow the Mormon Corridor and the Old Spanish Trail to Las Vegas and Los Angeles. In October of 1858 Simpson, with a small expedition of about 40 men and 5 army wagons left Camp Floyd and headed west. After going about 70 miles, winter weather started closing in and they returned to Camp Floyd. Simpson was optimistic about what he had seen and the following May, he started out again, this time to go all the way to Genoa, just south of Carson City, Nevada, and then to return by another route. This was the opening of the Central Overland Wagon Road. A few emigrants started using it right away and the following year its route was adopted by the Overland Stage and the Pony Express. A grove of trees can be seen about a ¼ mile south of SR 73. This is the cemetery where soldiers and other residents of Camp Floyd were buried.

Nothing remains but there is a monument (N40 15 38.0 W112 05 34.0) to the east across from the restored Stagecoach Inn. The visitor center has a small bookstore and is good for information. All that remains are the commissary building, where the museum is now, and the cemetery. The Stagecoach Inn was built in 1858 across the street from the commissary and served as a Pony Express stop. The inn was restored in 1959. The museum is open year-round from 9 -5 but is closed on Thanksgiving, Christmas and New Year’s Day. Day-use facilities include picnic tables with drinking water, restrooms, barbecue grills, fire pits and covered pavilions.

Fort Crittenden and Camp Floyd are one in the same. Camp Floyd was named after Secretary of War John Floyd. As the civil war flared up Floyd sympathized with the south, the base was renamed Fort Crittenden. 

Camp Floyd/Carson's Inn, Utah State Park, Fairfield, Utah (BLM 1977)  The camp was built in July of 1858 and in December of 1860, Camp Floyd was renamed Fort Crittenden. It was abandoned in July 1861 when the troops were called back to the east for the escalating north-south tension. The almost dismantled Camp/Fort which once housed up to 7000, and what little was left, has been taken by locals.

The last half of the Pony Express operations, it would have officially been known as Fort Crittenden though very little bears that name today, in fact everything official refers to it as Cedar Fort. The Cedar Fort /Stagecoach Inn State Park features a stagecoach hotel and small museum with artifacts and pictures of the once bustling fort.  http://www.expeditionutah.com/featured-trails/pony-express-trail/utah-pony-express-stations/