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Sourdough Trail

HARD 73 reviews
#42 of 139 trails in

Sourdough Trail is a 11 mile lightly trafficked out and back trail located near Boulder, Colorado that features a river and is rated as difficult. The trail offers a number of activity options and is best used from June until September. Dogs are also able to use this trail but must be kept on leash.

Distance: 11.0 miles Elevation Gain: 1,610 feet Route Type: Out & Back

dogs on leash

hiking

mountain biking

trail running

bird watching

forest

river

wild flowers

wildlife

bridge out

rocky

hiking
1 month ago

Not bad for the first couple of miles. As you get over 10k feet the snow obscures and blocks the trail. Hard climbing up and over but went until the end. Best to wait another week or so.

hiking
bugs
1 month ago

Hiked 6/1. Most dry/no snow up until about the first 1.5 miles or so. From there parts of the trail are blocked with large mounds of snow. Most are okay to walk across but with the snow melting it can get unpleasant at times. Turned around after about a mile and a half. Beautiful area though and will plan to come back soon after the snow melts!

snowshoeing
snow
4 months ago

Trail is well marked and had a great day of shoeing.

hiking
5 months ago

Nice, peaceful hike through the woods. trail was covered in snow buy had no issues in hiking boots. very lightly trafficked. only say one other person and dog.

snowshoeing
7 months ago

Quiet wooded trail, but very windy.

hiking
11 months ago

Ended up here randomly after the line at Mitchel Lake was at least 30 deep and not moving to pay $10 to be crowded on that trail... This was the first trail parking lot on the road to Rainbow lakes so I stopped around 2pm. This is a heavily forested hike that snakes upwards through several different layers of trees. I made it just past the 3.9 mark on the map before i turned around at 5pm. This was not a "Hard" hike by any means unless they were speaking of the length of the trail itself. This was the 23rd hike i did this season and I found this to be more "moderate." There were very few actual views through the trees and there is a site with ruins of some sort up by the environmental testing site. Lots of wood piles and old rusted metal cans and glass. Minimal activity along trail. Secluded most of the hike. Again seeing people just leave their bags of dog crap right along side the trail multiple times. Does someone come and pick this s-it up because it didn't seem like it. Why do people leave trash on the trail? Leave no trace? Disrespectful. Don't bring a dog if you can't clean up after your mess. Was a good endurance hike. Would have gone further if i had started earlier. Gave it 3 stars because of the limited views and dog waste.

hiking
11 months ago

Drive ~ Not worth the far drive up unless you are going to camp and stay overnight. Drive is windy and nauseating... very slow going. Dirt road to get to trail is terrible! Must have AWD or 4x4 to traverse. Single lane only in most places = treacherous and dangerous. Trails ~ This was a moderate to hard hike. VERY rough and rocky. We went with kids and dogs and had a few stumbles and falls. Yikes. Trail markings not really clear between off-roaders/4x4 and hikers. We were nearly run over several times because we were on an incorrect pathway. No bathrooms or public use areas which I had read in another review there was some. The one area that looks like you can access is actually private property and says no trespassing. Regardless of these concerns, the scenery was nice and the pines smelled lovely. We did have a fine time, dogs had fun and being in the trees was cool - lots of cover and shade. Probably wouldn’t go again just because of the drive time and treacherous nature of the off-roads. Tags ~ kid-friendly, kids, dog-friendly, dogs, dogs on leash, hike, hiking, trees, nature

hiking
Sunday, June 17, 2018

Gorgeous hike through the forest during a light drizzling rain. Saw less than a dozen hikers, bicyclists, and runners - not busy at all.

hiking
Monday, May 28, 2018

nice up and down. a few scenic views. some shade

hiking
Saturday, May 26, 2018

Well marked trail. Not sure why this is rated difficult; it’s a good hike but the only challenging part was the amount of snow still here. Ended up here due to a road closure, no summit but a very secluded & quiet trail.

hiking
Sunday, May 13, 2018

Went on 5/8. We were aiming for Rainbow Lakes but the road was closed so we opted for this trail instead. Much of the trail was still packed with thick snow. i didnt have snowshoes so a couple parts of it were a struggle, and I had to carry my little dog, lol, but it was a laughable and doable challenge. We only made it to the first creek then turned back. Trail is well marked which was much appreciated with all the snow cover. There were two sections that opened up so you get a nice view of the snow caped mountain across the way. Oh and there's a teepee!

hiking
Monday, April 02, 2018

Up until the bridge (even a mile or so after), was packed snow, no traction or snowshoes needed. After that, started to punch thru and didn't even make it halfway and lost the trail at one point due to snow drifting. Recommend snowshoes after bridge based on conditions today.

hiking
Tuesday, March 27, 2018

Currently mostly snow covered with a hard pack. No spikes or snowshoes needed!

snowshoeing
Wednesday, March 07, 2018

Super great! We got there early in the morning so there was plenty of snow. We saw a couple of people on the way but we mostly had the trail to ourselves. On the way down it had gotten quite packed down and there were lots of people.

hiking
Sunday, January 21, 2018

Fun winter hike! There’s snowpack on the trail but not enough that we needed special equipment. Snow boots worked fine. We started at South Sourdough trailhead and hiked around 1.5 hours, then turned back. There were people doing off trail skiing and snowshoeing. The portion of the trail we did was fairly easy. Uphill but at a low grade.

hiking
Sunday, December 03, 2017

Great walk and not too many people on the trail. Good dog walk too.

Wednesday, October 25, 2017

Started near Brainard Lake and went a few miles. Beautiful walk through the woods. I can see where this would be fun on a bike or snowshoeing. The trail is well marked.

Friday, September 08, 2017

moderate trail well marked. beautiful landscape and different terrain. well shaded and would recommend to anyone

hiking
Sunday, September 03, 2017

Great Sun. Morning. Not sure why it's rated hard...very mellow but we only did 1/2 from Gateway parking lot (free right by Brainard Lake entrance). So we went about 5miles out and back. We needed a mellow walk and this was really nice and gentle. Full is all day so definitely picnic and stopping at Peace Memorial Bridge is a good location halfway to do that.

Tuesday, August 08, 2017

Solid, moderate trail to get to Brainard Lake without driving in via Roosevelt entrance. You can find the trailhead at the free parking lot to the right of the parks entrance. nice mellow hike through pines and aspens. beautiful creek.

trail running
Sunday, June 25, 2017

a great trail for running. not many people. gentle ascent and wooded. a few creeks along the way for the pooches to get water.

hiking
Friday, April 28, 2017

There was a lot of snow.

snowshoeing
Monday, February 06, 2017

This is a trail we always end up at for snowshoeing! It has a lot of snowpack and is dog friendly, an essential for a good trail. Not too many people this day, it was snowing a bit but the conditions were great otherwise. More of a trail, not too much to see through the trees and the trail is a bit hard to navigate the dog friendly parts, but good overall!

hiking
Friday, August 14, 2015

I hiked a bit on the segment by Beaver Reservoir this month. There's an extended foot bridge over Beaver creek which is marked "Closed". This seems to be due to some missing/rotted boards and missing hand rail over the deepest part of the creek. It is safer than trying to ford the creek but it's definitely "use at your own risk".

mountain biking
Sunday, September 07, 2014

As the description states, mainly used for trail running and mountain biking. This is a very strenuous trail that is not recommended for sight seeing or a nice leisurely family hike. This is a very difficult and extremely rocky trail.

hiking
Friday, July 18, 2014

I simply love this trail!! It has been the subject of so many fun stories and adventures like this one: http://www.thescoop303.com/bullwinkle-the-bear-and-the-great-white-burly-dude/. This place has so much to offer and it is great all year around, I make it up here once per year!!!

hiking
Wednesday, June 11, 2014

Uphill trail that is fairly easy hike. About 15 minutes up you are allowed to camp and are currently allowed to have a fire. A buddy and I hiked in about 4 miles and camped over night was a good time and would do it again downhill was super easy!

mountain biking
Wednesday, June 20, 2012

Exit at University of Colorado Mountain research station, trail up ahead on right. This trail is very strenuous and 90% up hill, when heading north on trail. They call it north sourdough. Their are jagged rocks that cover whole trail all 6 miles up. It is fast down but beware, I am an advanced rider and my wrists killed me at the bottom and I'm on an all mountain bike. Little traffic also. Over all great ride, nice to get out city and hot temps and HIGH in the mountains :) 6/20/2012

mountain biking
Saturday, August 07, 2010

My Experience I started the ride at the Sourdough Trailhead off Country Road 116. The trail was well marked, and I was eager to ride on this sunny day. Within 5 minutes I was puffing, panting and cursing the baby heads, but I kept going, telling myself things could only get better!!.. Well, things only got worse. The lose rocks combined with the root carpet was killing me, and I was having traction issues that forced me into higher gear, a gear that was slightly too high for this ride, and I was knackered with about 2.5 hours ahead of me. I kept my head high, assuring myself it was going to be worth every minute of the grunt. But it never came, after a 2 hour slaughter, I reached the turn around point.. now I knew for sure that I really did not like this trail, it was like riding on a dry creek. Yes, the ride back was much faster, about 40 min. but it was a hell of a bumpy ride, and I was lucky that I actually managed to stay on the bike. This trail really confuses me, cos quite a few people recommended it, the books say it is the BEST singletrack in the Boulder area, and I read it was a very scenic trail.. ??? I, for the life of me cannot see what is appealing with this trail.. I am even seriously considering doing it again, just to see if I missed something along the way!! Other Info: Traffic on Trail : Two Mountain Bikers from Nebraska, and One Down Hiller walking his (very nice) bike Wild Life : None Scenery : None at all scenic (in Sept) Other : This trail is like riding on a dry creek My Trail Rating : 3 / 10 Trail Stats & Information Nearby City: Ward Length: 12.2 total miles Trail Type: Out-and-Back Skill Level: Technically moderate. Physically moderate to challenging Duration: Advanced Riders, 2 2.5 hours; Intermediate Riders, 3 3.5 hours Season: May to October Trailhead Elev: 9200 feet Top Elev: 1020 feet

hiking
12 days ago

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