The Denver, South Park & Pacific began construction in 1872, and was founded by a prestigious group of Colorado businessmen including John Evans, David Moffat, and Walter Cheesman. The general idea was to build a mountain narrow gauge railroad up the South Platte River, across the South Park and on to Leadville with a branch over Boreas Pass to Breckenridge. Rails were laid across South Park and reached the site of the future town of Como in 1879. Como was near the point where the route over Boreas Pass split off from the route west over Trout Creek Pass. This, combined with the nearby coal deposits, made Como a logical choice for a division point. At the time, the place was called the Stubbs Ranch and the site was purchased by the railroad. As Italian miners arrived to work the King Coal Mine, they named the town Como after Italy's Lake Como.

By June of 1879, there were a dozen wooden buildings and sixty to seventy tents. It was the temporary end of the track, and many of the residents were transients who would move on as the rails advanced.

The railroad constructed many buildings in Como which still stand today, including the stone roundhouse built in 1881. A brick hotel was constructed, only to be destroyed by fire in 1896, then rebuilt. A depot with a waiting room, ticket office, baggage room and platform was built. A machine shop and blacksmith's shop were also constructed along with various storage buildings.

Como was an instant town populated by coal miners and railroad workers. By 1881, the town had 500 residents. Train crews coming in from Denver, Leadville, or Breckenridge used Como as a stopover place. Day and night, the whistles of steam locomotives could be heard, and the smell of coal smoke permeated the air as passenger and freight trains came and went to various destinations.

In 1880, work began high in Chalk Creek Canyon on the Alpine Tunnel at an elevation well above 11,000 feet. This was the first tunnel drilled under the Continental Divide, and when it was completed, the railroad continued on into Gunnison. At the same time, the line over Boreas Pass into Breckenridge was completed.

Incorporated in 1883, Como's business district included a general merchandise store, a post office and a bakery. There was also a barber shop. A combination saloon and restaurant was located in the downtown area. The I.O.O.F. (Independent Order of Odd Fellows) hall was a two-story structure with the lodge room and office on the first floor and a dance hall upstairs. Wo Lee operated a laundry and nearby was a confectionery store. Facing the Pacific Hotel was a lunch room, a drug store and a pool hall. Other saloons in the business district included Allen's Corner Saloon, the Elkhorn Saloon and Delaney's Turf Saloon. Como's churches included Episcopal, Methodist and Presbyterian, as well as Catholic. Como also had it's own town hall, which collapsed during the winter of 1971. Como's post office has operated continuously since 1879.

As mining declined, so did the need for a railroad. As rail traffic was reduced, the number of people living and working in Como also declined. The Alpine Tunnel was closed permanently in 1910. The Boreas Pass line also closed this same year, but by court order, reopened in 1913. In 1935, the wood frame addition to the stone roundhouse burned to the ground, doing extensive damage to a rotary snow plow and two locomotives. A year later, application to abandon the entire railroad was submitted to the Colorado Public Utilities Commission. It was granted, and in 1937, the last scheduled passenger train left Como for Denver thus ending the narrow gauge South Park line. The coal mines had been closed for a long time, and the gold in the placer deposits in Tarryall Creek were exhausted. By 1940, Como began its decline into semi-ghost town status.