Mountain Biking Winter Park to Boulder via Rollins Pass (aka Corona Pass) and Jenny Creek Trail
If you happen to find yourself in Winter Park with a mountain bike, a way to shuttle a car to Boulder and a hardened countenance, then this ride is for you. There is a lot of history surrounding this old rail route, so please head over to the good folks at Wikipedia to learn more.
At 8 am on a crisp late August afternoon (2012), we began the ascent to Rollins Pass just north of Winter Park at start of Country Rd 80, aka “Corona Pass Road.” The entrance to this road is off Highway 40, and there is a nice commemorative sign.
After double checking our gear, tire pressure, and that at least one of us was wearing a kit worthy of such epic nature (Rapha), we began the journey up the western side of the Continental Divide, uncertain what exactly would lie ahead. Fortunately, on the western slope, what laid ahead of us was a relatively well-maintained dirt road that anything, including cyclocross and mountain bikes, four wheelers, and Chrysler K-Cars, can safely arrive at the top of the pass from the west (Winter Park) side. Going down the east side is another matter altogether, however…
We were having a great time, just lolly-gagging along, enjoying the beautiful scenery as we climbed out of the Winter Park valley.
We were even reminded to watch our manners and share the road with our motorized, four-wheeled, off-road brethren.
There were some perfectly cut switchbacks to enjoy as well. After having backcountry ski-toured on poorly designed, inefficient, lumbar road switchbacks, I have a new appreciation for a good turn.
Pretty soon, however, we began hearing thunder and noticing the sky quickly darkening to the north. “Smells like rain,” I sagely observed.
Soon, we came upon our first great landmark of the day – the Riflesight Notch Trestle and Tunnel. The tunnel is long since been closed/collapsed, but the trestle is still a sight to behold.
For comparison, this is what it looked like in 1903, which the train went over the trestle, looped down the side of the mountain, then came back through a tunnel underneath the trestle, not too dissimilar to the flyovers we cyclocross racers are so fond of (image credit: Wikipedia):
More pictures of the trestle, just because trestles are cool and unusual in my day-to-day life.
With the thunder getting closer and a few lightening strikes far off north, we decided to make haste for the pass. We also decided it would be quite prudent to keep each other within earshot in case we were caught exposed during a storm. According to our maps, we weren’t far from the top of the pass, so we motored. But not before Larry could document the absurdity and embarrassingly poor aesthetic of a GoPro helmet mount.
So, off we go, now riding north, right smack toward the storm and into the wind.
I really liked what I was seeing now, beautiful alpine lakes.
Brian was pushing the pace, so we made the pass very quickly.
We had reached the top of Rollins/Corona Pass at 13.9 mi, which took us about an hour and 50 minutes. We could have gone much faster, but we did stop several times for photographs, glances at the map, and general merrymaking. The storm seemed to be holding, at least initially, so I took some time to look around a bit. A trail leading north from the pass parking lot seemed inviting, so I followed it, and I spied another sign, so I took a picture of that one too.
Turns out, this trail is part of the 3100 mile long, Mexico-to-Canada, Continental Divide Trail. What I soon saw was breathtaking. King Lake was nestled into a breathtaking basin. A trail led down to the water’s edge, but I didn’t have time for nonsense such as hiking.
As mentioned previously, I did have my GoPro on me that day, so here’s the edited footage of King Lake, crossing the twin Devil’s Slide Trestles, and all the beautiful scenery, set to a handpicked Calexico soundtrack.
Back to the story at hand…
The wind started howling from the north, so I figured I’d better get back to the task at hand (not dying in a thunderstorm while mountain biking on an exposed ridgeline). I caught back up with the other guys who have more sense than I do but were waiting patiently. After a brief map consult, we decided that we should take the second easterly oriented road that took us through some “road closed” barricades, and off we went, teetering along the ridge, following the old railroad. Below, I thought I should include a Google Earth snapshot of the routes one can take. There are two roads that will take you to the Needle’s Eye Tunnel and the Boulder Wagon Road (BWR). We decided to take the old railroad line, which cuts alongside the ridge going east, and is the more northern of the two roads. The southern road, cuts higher along the ridge, so it’s probably a little safer, but it doesn’t include the trestle crossings that the railroad did. My GPS data trail is outlined in blue on this screenshot. Mind the compass – this screenshot is with an “east is up” orientation for the purpose of clarity.
Realizing what the men and women went through before our modern conveniences to get from point A to point B, especially in the mountains, gives one great pause. The gravity of the fact that we were hooting and hollering while riding modern mountain bikes along the same route tourists and workers would have done a hundred years ago hit me like a sledgehammer. We were soon ripping east on a slight decline at over 20 mph on the side of the mountain with jaw-dropping views to the north and east, and the earth falling away at 1000 ft below. Pretty soon, we came to a slightly technical section of fallen rock.
Once through, we got our first glimpse of what we had been after- the Twin Devil’s Slide Trestles, so named for their precarious perches and deathly drop-off. Crossing these trestles was certainly a high point of the whole day (and trip).
Once across the creaking trestles, it was another mile or so of fun downhill two track to the Needle’s Eye Tunnel road. The old railroad path we had taken joined with the other road that followed the ridge higher and which have been an automobile/service road.
Google Earth GPS data of our course, this time, with a “north-is-up” orientation. My GPS data path is in blue.

Google Earth screen capture of our route finding from Rollins Pass to Needle Eye Tunnel, and down the Boulder Wagon Road to the Jenny Lake Trail near Yankee Doodle Lake.
Here, we realized that we didn’t know the map beforehand as well as we thought we had. Also, the maps that were available to us didn’t reveal all the trails and roads that were in plain sight to us. So, with a little luck and a lot of route-finding knowledge, we rode down to check out the Needle’s Eye Tunnel anyway, despite knowing that it had been closed for many years due to a falling rock that injured a worker.
So, we road back to the “Needle’s Eye Tunnel Closed” sign, and made down the old Boulder Wagon Road. I learned something that I hadn’t known before – wagon roads are VERY steep. Switchbacks probably hadn’t been invented yet, so the gradient going down this thing was 25-30% (verified by STRAVA). Cameras and GoPros don’t even come close to conveying gradients like these.

Boulder Wagon Road (switchbacks didn’t appear to be original, as the original trail went STRAIGHT UP the mountain).

View back of the iron-rich mountainside near the Needle’s Eye Tunnel, taken from the Boulder Wagon Road.
The Boulder Wagon Road (BWR), does not appear to be maintained, and it is VERY rough going, filled with large rocks. Going down this way would be extraordinarily difficult with a cross bike or rigid mountain bike. (Hipsters, don’t you even think about bringing your single speed Schwinn or Nishiki down this way). Near Yankee Doodle Lake, the trail flattened a bit, and we came through another “Road Closed” sign. This time, there was a trail marker for what we had just been on, Trail 501, which must be the BWR. According to the NFS map, the 501 turns into the Jenny Creek Trail (#808) here.
Through some minor-route finding and navigation and creek crossings, we took this very rough and somewhat steep trail down to the Eldora ski area, and boy, were we ever thankful to have found our way through thunder, rain, and wilderness back to the edge of civilization.
From here, we went through Nederland, and climbed up to the entrance for Magnolia off the Peak to Peak Highway. Beautiful scenery along this road, famous for it’s 20% gradients coming out of Boulder Canyon (the other direction).
From here, it was a leisurely ride down the shallow sections of Boulder Canyon and back to AJ’s home for some food and beers.
So, the trip came to an end, but not without plenty of laughs, beers, and food to share. This is what cycling is about. A challenge together with close friends through wild country and history (and living to write about it). Peder
The stats:
- Total mileage: 45.19 mi
- Elapsed Time: 4:11:40
- Average Speed: 10.8 mph
- Maximum Speed:46.8 mph
- Total Ascent: 3886 feet
- Total Descent: 7065 feet
The gear:
- Yeti ASR-5 carbon, full suspension, 26er MTB, stock 2×10 XTR setup, with Schwalbe Nobby Nic tires (tubeless setup)
- Small Camelbak race hydration system + one water bottle on frame
- Topeak seat post rear mounted rack with touring bag
- Still cameras and GoPro
- Two of the other guys rode hard-tail 29ers with great success (one carbon Giant, and one aluminum Scott).
- Black Rapha Pro Team bib shorts, black Rapha Classic Jersey, all mated to S-Works MTB shoes (gotta look good, I suppose)
Fantastic job, Peder! Really does the day justice. Hadn’t really looked at the stats before. We went up almost 4k feet! Can’t wait to get back out there.
You a Kraftkwerk fan?
Was an awesome day for us. Did you see me put Larry into the gutter when the “road” narrowed before the trestle on the video? Ha!
BIG Kraftwerk fan now, thanks to you. I’ve been spinning their “Autobahn” vinyl LP a LOT lately.
Wow, this looks like a fantastic trip!!!!!!!!!
Nice, very nice write up! What map did you guys use, and where did you get it? Thanks!!
Thanks Ryan. I think the map we used was just a National Geographic map, but I’m unsure which one it was. There’s certainly some confusion about the top of the pass on how to get back to Boulder. However, it’s pretty obvious what you need to do, once you’re up there.
Nice write-up. We were doing some ATV riding last weekend and hiked from near road by Yankee Doodle over the Needle’s Eye tunnel and across the Trestles. We could see that trail over the divide in the distance from the Trestles. Do you happen to know how many miles it is from Needle’s Eye Tunnel to the end of the trail in Winter Park?
Round about 16-18 miles from Needle Eye Tunnel to US 40 then about 2 miles north to Winter Park. What ATVs were you using? We saw some gentlemen up there on the east side on 4 wheel ATVs hunting.
Nice report. I have ridden this route (the other direction) several years ago with a visiting Norwegian friend. Your report and photos reminded me that I need to pedal this again!
It really is a great route. Enjoy, and let me know if you post a ride report!