Caution. While this knowledge is powerful, mountain flying is wrought with risks and unpredictable variables. Exercise caution when attempting the mountain crossings described in this article.
The Continental Divide
The Rocky Mountains bisect the North American continent like a massive wall, an upheaval of terrain so immense that even the valleys are higher than most of the mountain peaks of the eastern part of the country, making its moniker "The Continental Divide" very accurate. The state of Colorado boasts more peaks over 14,000 feet than any other, and as a result, represents a significant obstacle for crossing by light aircraft. Outcliming terrain is usually not an option, as the service ceiling of most normally-aspirated piston aicraft is a limiting factor, making strategic routing a flight planning necessity.
This article aims to outline many of the most popular and navigable mountain passes of the Colorado Rockies, but is by no means the last word.
A word of caution
This article illustrates numerous ways one might cross the Divide. Ultimately you must balance all the individual factors into your own personal decision-making regarding "go/no-go" and route. By no means are these the only route possibilities.
This document is concise, perhaps lending the [false] impression of "Follow one of these routes and you're good to go." Nothing could be further from the truth. Colorado's section of the Continental Divide has many of the highest peaks in the lower 48, some of the most rugged terrain and often high winds on the clearest of days. It is not unusual to see winds at the passes regularly exceeding 50 to 80 mph throughout the winter months. Moreover, the Divide often exhibits unusually high pressure gradients within less than 100 miles (i.e. the author has seen 30.57 near Leadville while Denver reported 29.93 ish).
Please take everything here with a large dose of skepticism. Do your own follow up research. These routes are merely one item amongst many factors to consider for your go/no-go decision to cross the Divide.
The snow-capped textbook peaks of Hayden Pass await those flying a southerly route.
Waypoint entry for various devices
Each route includes a list of waypoints. If you're reading this on your iPad, the Foreflight 
button should open the route in ForeFlight, but for others you may have to enter the routing manually. It seems every time one reads an article that lists waypoints, one ends up having to Google the correct format to translate whatever Lat/Long format the author provides into something compatible with your app. Here are a few links to help you out in that process:
Waypoints are close approximations of the points throughout a route. For example, waypoints may show you going straight between Breckenridge and Copper Mountain whereas you would use common sense and follow I-70 around. In other words, use the waypoints as guidelines— not as gospel!
Main routing options
The Google map below shows 7 route options for crossing Colorado's Continental Divide. For each route, we've listed a few pros and cons, as well as some notable comments— these are individual opinions which are certainly not absolute nor necessarily complete. Again, read everything with a highly critical eye.
The main routing options table of contents:
If you wish to utilize these routes in your own map, here is a link to a Google Earth KMZ file. If you have Google Earth (free desktop & mobile app) you can use this KMZ file to display all of the routes listed in this document.
For comparative purposes, all routes start with Denver International KDEN. Of course, pick your own starting point East of the Continental Divide. Similarly, all routes end with Grand Junction, Colorado. Having the same starting and ending point provides one with comparative distances.
Colorado Department of Transportation maintains mountain AWOS stations. Similarly, one can get a good idea of current mountain weather from any number of web cams around the state. Weather Underground has a good stable of cams. FlyColorado.org maintains a good page of usable weather cams for pilots too.
Some pilots might consider following Interstate 70 as a safer option given it is easy to see and offers a landing spot if necessity requires. This is not recommended due to having to be up well over 14,500' to safely cross Loveland Pass on even the calmest of days. That exceeds the service ceiling of many light aircraft.
Regarding Wilkerson Pass
Wilkerson Pass is directly west of Colorado Springs. It's a little less convenenient, because to get there, one has to worm past/through the Air Force Academy airspace and the Colorado Springs class C airspace, not to mention there are a number of military high-speed low altitude jet training routes just south of it on the other side.
If the weather/winds are such that no options exist other than using Wilkerson Pass, perhaps consider using one of the Southern Routes outlined in this guide.
Northern Route
| Distance |
Map |
| 267 nm |
map |
| Routing |
| KDEN 40.94°N/105.74°W 40.94°N/106.22°W 40.39°N/106.64°W 40.23°N/107.53°W KEEO KGJT KEEO KGJT |
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Views from the Northern Route
Pros
- One can do this entire route below 10,000' —this is the only route listed that enables one to remain below 10,000' for the entire route.
- On hot days, or if engine performance is a bit lacking or aircraft loading is "heavy" the lower overall altitude saves one from having to climb up high
- Not needing to climb up higher typically offsets the additional mileage of this route
- One isn't faced with the steep climb out near the foothills, which having to stay below the floor of Denver's Class B airspace requires on more direct routes to the W out of the Denver area
- One avoids transitioning through the often busy airports and air traffic on the W side of Denver (e.g. Erie, Longmont, Boulder, Rocky Mtn Metro)
- You fly close enough to Rocky Mountain National Park to see some of the surrounding scenery
- The few mountain crossings are comparatively short
- Meadows abound where forced landings are possible
- The Colorado Springs-Denver area, particularly in late winter/early spring, is known for having a weather pattern referred to as an "Albuquerque Low"—creating low ceilings with an uncommon wind out of the East pushing upslope clouds. This route might get one across the Divide when all other routes are IFR.
Cons
- Additional mileage. Certainly a bit round-about.
- In the winter, major storms often track out of the NW, so this route would likely tend to close off with approaching weather sooner than other routes.
- Due to prevailing winds, this route often has a strong headwind component
- Generally low population density all along the route (If you have to land and need assistance)
- Characterized by pine tree forests and rounded mountains. Not the sharp, jagged peaks of the Central and SW Colorado Rockies
- Within reason, wind over the mountains isn't generally as key a factor on this route as it is elsewhere
- One of the most conservative routes, if not THE most conservative route, over the Divide
- Check winds aloft at 9,000' & maybe 12,000'. Sources: NOAA ; Windy
Views from the Northern Route
Direct Route
| Distance |
Map |
| 190 nm |
map |
| Routing |
| KDEN 39.95°N/105.69°W 39.99°N/106.09°W KGWS KGJT |
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Pros
- The shortest route between Denver and points West
- Very scenic; Rollins Pass has evidence of the original narrow gauge route across the Rockies with the Needles Eye Tunnel and several wooden trestles; One flies over several ski areas (Eldora, Winter Park, Mary Jane)
- Further on one passes near/over Glenwood Canyon, which is anther very scenic Colorado area
Cons
- Requires a relatively steep climb out after clearing Denver Class B airspace on the West side of the metro area
- Generally requires flying at or above 13,000' for at least a short while over Rollins Pass
- Likely requires coordinating with the tower at Rocky Mountain Metro, and later Eagle/Vail airport, to safely transition through or near their respective Class D airspaces
- Before considering this route, please check upper winds at 9,000', 12,000' and 15,000'. If any predict winds at or exceeding 20 to 25 knows this route is NOT recommended!
- Low winds might be present as close as 10 miles from the pass—yet closer than that you might encounter much higher winds. A good rule of thumb is be at least 1,000' feet above the highest point for every 10 knots of predicted (or actually encountered) wind
- Definitely seek out experienced instruction in mountain flying before attempting this or any other of the following routes! Also consider reading "Mountain Flying Bible [Revised]" by Sparkey Imeson as well
- On a good day, one would want to be up to at least 13,000' on this route (when crossing the pass)
- If the clouds look like the photo below, STAY AWAY! Winds were gusting 50 to 70+ mph on the pass that day— not the place to be!
- Strong possibility of clear air turbulence or severe rotors with winds > 20 knots (personally experienced this!)
- The author has had to go as high as 15,000' to safely cross this route due to winds
Alternate Direct Route
| Distance |
Map |
| 200 nm |
map |
| Routing |
| KDEN 39.42°N/105.51°W 39.47°N/105.69°W 39.42°N/105.77°W 39.42°N/105.96°W 39.53°N/106.22°W 39.65°N/106.33°W KGWS KGJT [Follow I-70 from Breckenridge to Copper Mtn] |
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View of Breckenridge from the Alternate Direct route.
Pros
- If clouds or winds preclude the direct route over Rollins Pass, this route is a good next option.
- One can sometimes get through here when clouds obscure all the other passes (as seen here)
- Scenic past Breckenridge & Vail ski resorts
- Possible landing spots along roads the entire route
Cons
- Requires crossing three main passes—Kenosha, Boreas and Vail
- If clouds or winds preclude the direct route over Rollins Pass, this route is a good next option
- If winds are more than 20 knots, then one can get a venturi effect with much higher actual winds right in Boreas Pass
- Suggest one not think about this route if winds are at or greater than 30 knots at 12,000'
- Strong possibility for the presence of rotors with winds > 20 knots at 12,000'
- Due to high terrain all quadrants, the minimum altitude for this route is likely at least 12,000'
- Once across Boreas Pass, one has to transition through a relatively narrow canyon following Interstate I-70 between Frisco & Vail (see route map above.) If winds at 12,000' are 20+ knots this is not recommended
- Boreas Pass is the old narrow gauge railroad route between Denver and Breckenridge; It is a dirt road today. It starts by the small "town" of Como off of Highway 285
- The keys here are a) Being up in the 12,000' altitude range to safely cross Kenosha Pass and being able to get across Boreas Pass (elevation 11,493') at no less than at least 12,000'++
Southern Routes: Introduction
If a storm system is moving in from the NW, then one of the Southern routes may be your only option to get across the Divide. You'll note that these routes are significantly longer—as much as twice as long—as the Northern routes.
The routes are presented in typically "weather-dependent" order. In other words, as incoming storms out of the NW move across Colorado, the first route to "close" will be the Poncha Pass route. It is not unusual to see Poncha Pass with clouds right down to the deck and yet have nearby Hayden Pass open.
Similarly, once one is in the San Luis Valley region (e.g. Alamosa, Del Norte, Monte Vista) Wolf Creek pass may be IFR. So that's the case, one can try the Cumbres Pass option (last option below).
The Southern routes generally require one to be up at over 12,000' or more. If upper winds are greater than 15 knots or so, an altitude of 13,000' is warranted over the passes themselves.
Photo: FlyColorado.orgNote the swirling, wind-lofted snow near the peaks in the background. This can can be indicative of severe mechanical turbulence from rotors— mountain pilot beware.
Southern Poncha & Wolf-Creek Pass Route
| Distance |
Map |
Cams |
| 375 nm |
map |
videocam |
| Routing |
| KDEN 39.41°N/105.5°W 39.48°N/105.7°W 39.42°N/105.77°W 38.91°N/105.98°W KANK KANK KRCV 37.63°N/106.73°W 37.48°N/106.81°W KDRO 37.33°N/108.17°W 37.7°N/108.38°W KGJT |
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Crossing Trout Creek pass toward Buena Vista & the Collegiate Range
Pros
- If clouds or winds preclude the previously listed routes, this is a more Southernly option which avoids the 14,000'+ Collegiate Range peaks
- One can sometimes get through here when clouds obscure other passes to the N & W
- Once past Kenosha Pass the terrain is characterized by broad, very large, flat areas until the next subsequent pass.
- Possible landing spots along roads the entire route
- Poncha is a relatively short pass to cross
Cons
- Requires crossing four passes—Kenosha 9,997', Trout Creek 9,467', Poncha 9,010' and Wolf Creek 10,856'
- Wolf Creek pass is the ultimate bottleneck, as the mountains surrounding it are rugged
- If winds are 20+ knots, the approach to Kenosha Pass can be turbulent. If there is any wind recommend at least 12,000' through this initial section
- Wolf Creek pass is a somewhat longer pass to cross—once you're in the Wolf Creek pass transition you're pretty much committed
- If winds are 30 knots or greater, this route is NOT recommended
- If winds are 20+ knots, Wolf Creek pass is NOT recommended
- Once again, initially requires crossing Kenosha Pass (9,997'), the approach to which can be windy and bumpy if there is any weather system approaching.
Pros
- If clouds or winds preclude trying to fly over Kenosha Pass, then you're left with trying a more Southernly route such as this
- The advantage here is that one can get into the Alamosa (San Luis Valley) basin by only crossing one pass—Hayden 10,709'
- If you can safely get into the San Luis Valley, you have options to continue further West
Cons
- Hayden Pass, though short, has steep E and W aspects. Hence if winds exceed even 10 knots, one MUST give this pass a healthy margin—at least 2,000'
- The author has seen Lee and Windward side down/up drafts exceeding 1,500'/minute with upper level winds only in the 15 knot range
- Due to the venturi effect, Hayden pass can generate higher winds than those seen only a few miles E or W
- If winds are 30 knots or greater, this route is NOT recommended
- Again, if winds are 20+ knots, further on, Wolf Creek pass is NOT recommended
- Crossing Hayden and Wolf Creek passes requires solid mountain flying skills. These passes have extremely rugged terrain in all quadrants.
- Once again, Wolf Creek pass takes some time to transition through. Once having made the decision to proceed and into the area of Wolf Creek pass, if winds or weather are an issue turning around will be challenging to say the least
- No matter what the weather or winds, recommend at least a 2,000' above-the-pass buffer to safely cross
Southern Mosca & Wolf-Creek Passes Route
| Distance |
Map |
| 419 nm |
map |
| Routing |
| KDEN 38.21°N/104.24°W 37.8°N/104.98°W 37.74°N/105.48°W KRCV 37.63°N/106.73°W 37.5°N/106.81°W KDRO 37.33°N/108.16°W 37.7°N/108.38°W KGJT |
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Pros
- This route takes one down the Colorado Front Range to the East of Pueblo. If there is any upslope weather, this might potentially get one past such
- If clouds or winds preclude trying to fly over Hayden Pass, then Mosca pass (9,714') gives you an option to look at further South
- The advantage of trying Mosca pass is simply that of a possible shortcut into the San Luis Valley (Alamosa area)
- Again, if you can safely get into the San Luis Valley, you have options to continue further West
- Mosca Pass is almost a 1,000' lower than Hayden Pass.
Cons
- Mosca Pass, like Hayden Pass, though short, has steep E and W aspects. Hence if winds exceed even 10 knots, one MUST give this pass a healthy margin—at least 2,000'
- The author has seen Mosca Pass open when Hayden Pass had clouds to the deck
- Due to the venturi effect, Mosca Pass can also generate higher winds than those seen only a few miles E or W
- If winds are 30 knots or greater, this route is NOT recommended
- Again, if winds are 20+ knots, further on, Wolf Creek pass is NOT recommended
- Crossing Mosca and Wolf Creek passes requires solid mountain flying skills.
- See previous comments regarding Wolf Creek Pass
Southern La Veta & Cumbres Pass Route
| Distance |
Map |
Cams |
Notable peaks |
| 425 nm |
map |
videocam |
La Veta 9,426'
Cumbres 10,022'
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| Routing |
| KDEN 38.23°N/104.23°W 37.62°N/105.23°W KALS 37.01°N/106.48°W KDRO 37.33°N/108.18°W 37.69°N/108.37°W KGJT |
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Pros
- With any major weather system moving in from the N or West, this route is generally your last option—Ok, you could fly S to New Mexico, of even Mexico itself, but …
- Again, if you can safely get into the San Luis Valley, you have options to continue further West
- This route avoids Wolf Creek Pass, which as previously noted can be a bottleneck due to weather, winds or just plain rugged terrain
Cons
- La Veta Pass can have issues with winds, generating rotors off of the Spanish Peaks to the South
- If winds are 30 knots or greater, even this route is NOT recommended
- If you got through La Veta Pass, odds are that Cumbres Pass is "open." But, if not, one could fly even further S toward the Taos VOR, the towns of La Madera, El Rito and then up the Chama River Canyon back towards Durango (this option not shown)
Photo: FlyColorado.org
Approaching the East side of Wolf-Creek Pass area
keikflyer 
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