Page Type Page Type: Mountain/Rock
Location Lat/Lon: 39.98729°N / 105.29331°W
Activities Activities: Trad Climbing, Scrambling
Seasons Season: Summer, Fall
Additional Information Elevation: 7220 ft / 2201 m
Sign the Climber's Log


The iconic and mega-classic Third Flatiron is the most sought after climb above Boulder. Easily seen from all over town, the Third symbolizes the nature of Flatiron climbing. Attracting beginners and experts alike, the Third offers a tremendous variety of routes that appeal to anybody interested in standing on its lofty summit. This rock sees more climbers than all other Flatiron routes put together (most on the standard route) so expect some company.

Notable Routes

Here are a few of the most notable routes...

East Face Standard 5.4 - First ascended in 1906, this is considered to be one of the best multi-pitch climbs in the country (especially for beginners). It has giant bolts at almost every belay stance and most of the climbing is as easy as it is enjoyable. It is said to have been climbed in a variety of ways including roller-skates, cowboy boots and even in the buff. The giant painted "CU" that has come and gone over the years and can be clearly seen from town is climbed over in the middle of this route. This is given a "Top 10" rating by Gerry Roach. Don't expect to be alone.

Friday's Folly 5.7 - Another of Roach's "Top 10" climbs, this fine route climbs steeply up the west/soutwest face of the rock. It sits below the rappel anchors so watch out for descending climbers when on this route.

Winky Woo 5.4 - Another of Roach's "Classics", this route is said to be one of the steepest 5.4s in the area. It ascends giant jugs up the steep south face.

East Face South 5.2 - Yet another of Roach's "Classics", this route climbs the length of the east face. The lack of bolted belays keeps most climbers off although the climbing is close to the same difficulty as the standard route.

Northwest Passage 5.10b - A historic route, this climbs the imposing north face. The first ascent was a major achievement in aid climbing using expansion bolts.

Getting There

The Third is easily accessed by a number of popular trails beginning at Chautauqua Park. The one you chose depends on the route you are there to climb. I will leave it to the route pages to describe the specific approaches.

The ThirdClick for larger version.

Red Tape

The Flatiron's annual raptor closure shuts down all activity on the Third every February 1st until July 31st. Any unusual circumstances can reduce or extend the closure and a detailed list of all closures can be found HERE on the OSMP website. The closure area is clearly marked on the trails and it is a good idea to check the link before you go.
Do not be tempted to ignore the closures as you can be easily seen from all over town and will be met with a hefty fine. Activity like that could lead to extended or permanent closures. Please don't be "that guy" and ruin it for everybody else.

Only use clean climbing techniques so leave that hammer at home. This may seem obvious but I have discovered new pitons on routes recently.


There is no camping allowed in the Flatirons.

External Links

Here is a great interactive MAP of the area.

Here is a LINK to NOAA's weather site.

The OSMP website provides a ton of good information and can be found HERE.

A brief time-line of notable ascents can be found HERE on the Flatirons Climbing Council website.

An interesting article in the Daily Camera on the history of the giant CU can be found HERE.



Children refers to the set of objects that logically fall under a given object. For example, the Aconcagua mountain page is a child of the 'Aconcagua Group' and the 'Seven Summits.' The Aconcagua mountain itself has many routes, photos, and trip reports as children.