The 1917 Oltjenbruns Farm is an excellent example of a family farming operation, associated with both the farming boom of the 1910s and the dramatic changes in farming practices at the mid-twentieth century.  A German immigrant who operated several farms in Nebraska before moving to Phillips County, August Welper was a general farmer who planted dryland wheat and alfalfa and raised horses, cows, and chickens.

The town is situated at the center of the San Juan mining district.  Prospecting began in the 1860s, but it was not until 1871 that the first profitable silver vein was discovered in nearby Arrastra Gulch.  The late 19th and early 20th century residential and institutional buildings within the district reflect the prosperity brought about by one of Colorado’s richest mineral producing regions.  

The Sound Democrat Mill and Mine and Silver Queen Mine are a representative moderate-scale industrial mining and milling complex from Colorado’s period of hard-rock mining.  In 1894 mining began at the Silver Queen, followed by the Sound Democrat in 1898.  

The Shenandoah-Dives Mill, which was constructed in 1929, is an exceptionally intact example of a selective flotation mill reflecting the distinctive characteristics of hard-rock milling processes in the early 20th century Rocky Mountain West.

The circa 1904 -1910 Minnie Gulch Cabins site, including the cabins, dugout, and associated artifact scatters, represent a typical small residential and industrial complex associated with nearby mining during the turn of the 20th Century.  Intact groupings of this sort from the hard-rock mining period in Colorado are unusual. 

The Martin Mining Complex is associated with the mining industry in the San Juan Mountains and the Eureka Mining District.  The complex displays the development of industrialized hard rock mining and the transportation infrastructure needed to make such mining profitable in a rugged region.  The Martin Mining Complex is representative of the boom and bust cycle that was always present with industrialized mining.  The 1929 Martin Boardinghouse is one of the best-preserved and largest boardinghouses still standing in the San Juan Mountains.  More precisely, the Martin Boar

Located northwest of Silverton at an elevation of 11,400’ and closely associated with the development of the mining industry in northern San Juan County between 1877 and 1914, the Frisco-Bagley Mill and Tunnel complex epitomizes the speculative nature of early hardrock mining enterprises in the area as well as later efforts to revive the local mining industry by utilizing existing technology in new ways to increase efficiency and profits.

The narrow gauge rail line, constructed between 1880 and 1882, connected the rich silver mines of the Silverton mining district with the smelters in Durango.  The line formed an important transportation link for moving ores to processing centers and supplying the high mountain community with the necessities and comforts of life. 

The narrow gauge rail line, constructed between 1880 and 1882, connected the rich silver mines of the Silverton mining district with the smelters in Durango.  The line formed an important transportation link for moving ores to processing centers and supplying the high mountain community with the necessities and comforts of life. 

Outfit Tool Car 04351 is a boxcar originally built in 1897, reassigned as a work car in 1914 and again in 1927 to carry tools, parts, and supplies for rail crews in wrecker service along the rail line. The car is significant for engineering as a good example of a Class 6 boxcar.