August 24, 2024, starting at 9 am. Map handout starts at 7 am.
About 20 miles south of Silverton, Colorado and 29 miles north of Durango, Colorado. We call the area the Twilight Zone—west of Twilight Peak, accessed from Lower Old Lime Creek Road (off US 550 at Cascade Curve).
Coordinates 37.65429, -107.80164 CalTopo
An orienteering version of a Backyard Ultra. Tackle a new orienteering course every time period until no one else is left!
This event is conducted under a special use permit issued by the USDA-Forest Service, Columbine Ranger District.
Orienteering is competitive land navigation using only map and compass.
Beginner courses can be completed by following roads, trails, and other readily-followable linear features. Intermediate courses require some off-trail navigation, but usually provide you with opportunities (if you can recognize them) to constrain the chance for serious error. Advanced courses are usually as off-trail as possible, test a wide variety of skills, and are less forgiving of errors.
For this particular event, the following rules are in play:
There are eight different courses available. You can only complete each course once. Each course consists of somewhere in the neighborhood of ten or twelve controls. Each course is also rated for:
The par time is the theoretical time that a runner-of-a-certain-caliber ought to take for the course, assuming no navigational errors. For comparison, a par runner ought to be able to cover 6.076 km in an hour over perfectly flat and perfectly smooth terrain (this rather weird number derives from the Backyard Ultra tradition). Par times are adjusted for elevation gain, vegetation, and so on, and are validated with field testing.
To complete a course in the Last Person Standing:
The Twilight Zone comprises extensive forests and gneiss tablelands. The terrain is much gentler than either of our previous venues for the Lost One Standing (the Ouray Amphitheater and the Ironton Valley). Elevations range from 8,200 to 9,700 feet.
The area is about 85% forested with an average speed of slow run. Lower forests are dominated mainly by spruce and fir, with many small marshes (which will probably be relatively dry at the end of August). The higher tablelands have a mixture of aspen, ponderosa pine, clearings, intricate topography, and numerous rock features.
Two-and-a-half hour courses should make the best use of the mapped area. Extra time is given at night.
The map is LiDAR-based and mostly compliant with ISOM 2017-2 but with a few added symbols.
Located in the western portion of the map, this snippet features gentle topography, abandoned horse trails, four colors of forest, some open marshes, and some "formerly open" areas that are transitioning to young aspens (partially outlined with green dashes). Note the presence of two slope lines, showing a very broad saddle.
The eastern tablelands contain more intricate topography, some steeper ground, many rock features, a higher percentage of open land, and a fair number of individually drawn trees. Note that one set of green dashes represents an island of taller rather than shorter trees. Can you figure out which one?
A green X represents a prominent group of two or more trees. Also shown is our only symbol that is slightly nonstandard—dark gray instead of black for a passsable cliff.
Free camping is available at HQ Friday and Saturday nights. More generally, dispersed camping is also allowed the whole length of Old Lime Creek Road (the southern 1.5 miles are suitable for most vehicles--4WD medium clearance recommended beyond that).