Route: Sanitarado (Boulder, CO)

Colorado, US
21.5 mi
Vertical Gain
9,000 ft

Sanitarado is the name given to a route that lies primarily in the City of Boulder (CO) Open Space & Mountain Parks (OSMP), but also partially in Eldorado Canyon State Park. The route connects the summits of Mt Sanitas, Flagstaff Mtn, Green Mtn, Bear Peak, South Boulder Peak and Eldorado Mtn. It is about 19 miles long, and involves 8500 vertical feet of ascending (and descending). Most of the route is on trails, but the final roughly 1500 vertical feet on Eldorado Mtn are off-trail (and in an OSMP Habitat Conservation Area, which requires an off-trail permit for legal travel, see this page for more information.)

The Sanitarado (and the reverse route, known as "Eldoitas") has been done for by locals for decades, but few times have been recorded for posterity.  Bill Wright's trail running records site for the Boulder area lists himself and Mark Oveson as holding the FKT for Sanitarado at 7h49m (TH-to-TH), and Kreighton Beiger as holding the Eldoitas record at 6h56m37s.  No dates are given for these, so we are listing them here instead of in the FKT list.  They were certainly prior to 2011.

Note that Sanitarado is about a mile longer now than in 2011 because of the reroute of the Green-Bear trail. It's probably slower too because of damage to some trails in the September 2013 flood. Shadow Canyon is particularly rough now - hard to run down well.

GPS Track
Eldoitas.gpx285.11 KB


Andy Wacker did the Sanitarado in 5h7m37s on 11/29/2020.  BUT, he did not go to the actual summit of Eldorado Mountain, but over to the antennas instead.  While this has little to no impact on the overall time, it is important to know and follow the correct route for the FKT - that's part of the game!  Therefore, we do not consider Wacker's time the FKT, as impressive as it is.

Wacker reported:

Skyline plus! Nice weather. Pretty icy in parts. Took a wrong turn down Green and forgot to turn on Green-Bear, but great views for an extra mile. Felt good up Bear, and South Boulder. Had a good descent down shadow canyon, until I took my micro spikes off just in time to fall hard on my back. Made it to Edlo. Bought a day pass at the gate. Cool ascent up Eldorado Mountain until it became gnarly rock climbing on snow! Don't follow the exact ridge! Followed some footprints in the snow on the way down and had fun once I got off the technical part of the ridge. Fuel: honey stinger gel at green, performance chew on green bear, gel at 4:00 Awesome run! 11/10


  • Sanitas 18:33
  • flagstaff (four way intersection) 1:05
  • Green 1:33
  • Bear 2:25
  • South Boulder 2:35
  • Eldorado (missed it - just after 4:00)