For years, Union Pacific wanted improved rail access to Yellowstone's geyser basins and to Old Faithful Inn, that opened in 1904.

The planned route for the new railroad was through Marysville, up Warm River Canyon into the forested Island Park country, and on over the Continental Divide at Rea's Pass into what became West Yellowstone.

The matter was expeditiously resolved when Union Pacific decided to build the railroad through a new town one mile (1.6 km) west of Marysville named after the OSL Chief Engineer, William Ashton.

One of the two founding fathers, H. G. "Fess" Fuller, became the long-time Mayor of Ashton and the other, Charles C. Moore, went on to become Governor of Idaho.

Beginning in 1910, Ashton was the railhead used for the construction of Jackson Lake Dam in Grand Teton National Park by the Bureau of Reclamation.

For several years, materials and equipment were freighted by wagon from the Reclamation Building in Ashton to the dam site at Moran, Wyoming on what was known as the Ashton-Moran Road or Reclamation Road, as the locals called it, that ran 56 miles (90 km) over the north end of the Teton Range.

Union Pacific then built the Teton Valley Branch railroad to Driggs and Victor from Ashton and completed in 1912.

American Dog Derby Ashton, being at the head of the Snake River Plain and at the end of the Yellowstone moisture channel, has 20 inches of precipitation annually (according to usclimatedata.com).

It may have been Ashton's beautiful view of the Tetons, it may have been the happy cast of characters involved, but for whatever reason, by 1923, the American Dog Derby had captured the imagination of the western world.

Newspaper correspondents and newsreel cameramen came from distant cities seeking the inside story of the American Dog Derby while crowds grew to 10,000 or more people in this town of less than two thousand.

The buildup to and the results of the American Dog Derby were reported by newspapers and by newsreels in the Americas, in Europe, and elsewhere.

Shortly after the first settlers arrived in the 1890s, several canals were developed to divert water from streams running off the Yellowstone Plateau and Teton Range.

Some farmland, mostly to the east, is high enough and close enough to the Teton Range that crops can grow without irrigation due to increased rainfall.

The relatively high altitude limited crops to those requiring a short growing season such as grain and alfalfa.

The short growing season keeps the potatoes desirably small, and the long, cold winters create the ideal conditions for seed.

Ashton's winters clean the soil of these mold spores with a long, deep and killing freeze.

According to the United States Census Bureau, the city has a total area of 0.66 square miles (1.71 km2), all of it land.

This unusually high precipitation in the Ashton area is due to the geography of southern Idaho and Yellowstone.

This area marks the virtually easternmost extremity of the typical Pacific Northwest annual precipitation pattern, with its dry summers.