Ashton is a city in Fremont County, Idaho, United States. The population was 1,127 at the 2010 census, and it is part of the Rexburg Micropolitan Statistical Area. The district is noted for seed potato production and bills itself as the world's largest seed potato growing area.
In 1900, the Union Pacific Railroad, under the careful watch of the Oregon Short Line (OSL) and St. Anthony Railroad Company, brought the railroad into the Upper Snake River Valley from Idaho Falls to St. Anthony, Idaho, 14 miles (23 km) southwest of what became Ashton. The venture had considerable local support and official support from the LDS Church. Following successful construction and operation of the St. Anthony Railroad, Union Pacific, under the careful watch of the OSL and the Yellowstone Park Railroad Company, began plans for another railroad from St. Anthony to the Madison River entrance of Yellowstone National Park or to what is now known as West Yellowstone.