Ceran St. Vrain Trail / Miller Rock

Trail Meter: 

This ride is one of the funnest stretches of creekside singletrack in Boulder County...followed by a heinous climb up to Miller Rock. From the trailhead you ride downhill following narrow, twisty singletrack - super flowy with the occasional tough technical move. And don't fall on those technical spots either as the steep drop to South St. Vrain Creek has claimed more than a few collarbones over the years.

At the bottom of the singletrack descent, take stock of your will power. The climb up to Miller Rock is a doozie, and don't forget you'll be climbing back out to the trailhead. Miller Rock is well worth it, though, with some of the best views of the Continental Divide around. Local lore has it that a man named Miller took refuge on the rock after a lynch mob came after him for stealing a horse (think about how bikers feel about bike thieves). Miller, being such a smart thief, snuck on top of the rock where he waited the lynch mob out...until he starved to death the tale goes.

There are two ways to get up to Miller Rock, and they are both heinous. We recommend the counterclockwise loop as the hair-raising descent is super fun in that direction. Bring a map as the roads and trails get confusing around here. First you'll ride, push, and carry your bike uphill on a nasty jeep road that has degraded into fields of babyheads in places. Once you flatten out bear left at the second intersection and continue up the jeep road to the base of Miller Rock.

For a nice view and a sweet snack spot, get off your bike, walk around to the backside of the rock, and scramble up. Once you've had your fill of the expansive views, get back on your bike and head back the way you came (continuing uphill takes you to private property). As you retrace your steps, look out for singletrack heading off to the right of the jeep road you just climbed. The intersection is not marked. This singletrack descent goes from fast and flowy to downright death-defying. Have fun, but remember how far from civilization you are at this point. The pucker factor weeds a lot of people off this trail after the first attempt. Once you are safely at the bottom again, it's time to ride back up the creekside singletrack to the trailhead.


Ceran St. Vrain - Miller Rock GPX File142.54 KB
Ceran St. Vrain - Miller Rock Google Earth File5.27 KB
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Ceran St. Vrain Trail / Miller Rock Click on image to enlarge
Ceran St. Vrain Trail / Miller Rock Click on image to enlarge

T: 8 A: 7 C: 8

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6.25 mi.
1000 ft.
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