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Strange Structures – Howardsville, CO Quadrangle

Latitude: -107.609692
Longitude: 37.802494

As part of our amTopo map creation process, we import aerial imagery into our software to ensure roads, trails and other features can be accurately digitized. Sometimes we spot some pretty interesting things in the imagery, many which are clearly recognizable (Ancient Puebloan ruins, craters, flocks of sheep, etc.). Occasionally, we get stumped, however, as was the case when generating our Howardsville, Colorado 7.5 Minute topographic map.

Howardsville is located in the rugged San Juan Mountains of southwest Colorado, just east of Silverton, and rich in mining history. Abandoned mining structures and tailings are a common site along hiking trails and 4WD roads in the area, but while digitizing the Silver Lake Trail (formerly a mining road), we noticed several triangular objects that were unlike typical mine structures. These objects were all aligned in the same direction (uphill) and were casting shadows, implying they had some height to them.

strange_triangular_structures
Pointing the way to riches hidden in Arrastra Gulch? (Image courtesy of Google Maps )

After scouring the internet for some answers (we won’t discuss the lost productivity resulting from said search), we finally learned that what we were seeing are structures that were built by the miners to protect other structures from dangerous avalanches. These are commonly referred to as avalanche splitters or diverters.

avalanche_barrier
Protection for an aerial tram tower (Image courtesy of FishPOET)

In the image above, you can see how the stone and metal splitter provided up-slope protection for an aerial tram used to bring ore from the mines down to the mill. In the event of an avalanche, the splitter would dissipate the slide’s energy and deflect snow to the sides and away from the tram tower. Even though the splitter itself is dome-shaped, when viewed from above you see its triangular form. These splitters were strategically constructed in treeless avalanche chutes where miners and their mining facilities were at greatest risk during winter.

For those of you who are fascinated with strange and curious sites as seen from space, check out Weird Google Earth – plenty of mystery, history and beauty out there!

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Cascade Canyon Wye – Electra Lake, CO Quadrangle


Latitude: 37.5945
Longitude: -107.7777

For those of you who are rail buffs, you may already know a bit about this feature, or at least, its function.  The Denver & Rio Grande Western Railway historically operated between Denver and Salt Lake City, with numerous spurs connecting to the various mining and lumber towns scattered across the Rockies.  Today, most of the original line has long been abandoned and removed.  One particularly popular stretch still in operation, however, is a 45-mile section run by the Durango & Silverton Narrow Gauge Railroad (D&SNG), which takes tourists between these two quintessentially western mountain towns and follows the scenic Animas River through steep, forested terrain.

Located approximately 26 miles north of Durango, the Cascade Canyon Wye was constructed in 1981 to provide the D&SNG a place to turn around during winter excursions when heavy snow pack prevents the train from proceeding all the way to Silverton.  In addition to the triangle-shaped track that allows the train to make a three-point turn and reverse direction, a structure has also been erected on the banks of the Animas that serves as a lunch area for winter passengers.

The next few miles of track north of Cascade Canyon Wye pass additional historic sites, such as the impressive steel Tefft Bridge built in 1887 (named for an early forest ranger Guy Tefft), and an abandoned boiler.  Per Robert T. Royem, author of America’s Railroad: The Official Guidebook, this wood and coal powered boiler came from Locomotive 32, the “Gold King” and was sacrificed by the side of the tracks in order to power a sawmill and other machinery used by the railroad company around 1910-1911.  A little farther up canyon, Cascade Siding (no longer in existence) was used by ranchers to load and transport livestock from the area.  A section house was also located here at one time, and the siding saw additional action as recently as January 2001, when the D&SNG assisted the Colorado Division of Wildlife in releasing a number of bighorn sheep into the surrounding Weminuche Wilderness.

To anyone planning a visit Southwest Colorado: be sure to check out Durango and ride this infamous train (think Butch Cassidy & the Sundance Kid).  You will revel in the natural beauty of the region and see plenty of local history come alive while on the rails!