Hall Ranch, Bitterbrush and Nelson Loop Trail is a 9.5 mile moderately trafficked loop trail located near Lyons, Colorado that features beautiful wild flowers and is rated as moderate. The trail offers a number of activity options and is accessible year-round. Horses are also able to use this trail.

9.5 miles
1,505 feet

kid friendly



horseback riding

mountain biking

nature trips

trail running




wild flowers



no dogs

The Bitterbrush and Nelson Loop Trails are fairly difficult mountain bike routes that form a lasso trail near Lyons, CO. Unlike many of my other trail guides, this one is definitely a little more strenuous and technical. If you are riding a bike, prepare for steep climbs and rapid descents. There are some tricky corners and numerous rocks and roots in the trail. There is also great scenery, lots of wildlife, and a heck of a roller-coaster ride. Although this trail is good for hiking, many hikers choose Nighthawk Trail, which runs off of this trail and takes a similar route. HISTORY: In 1885, Edward Lyon settled the land that later became Hall Ranch. The sandstone quarries just to the east of Hall Ranch are made up of 52 smaller quarry pits, and these were also established by Edward Lyon. Electricity was first introduced to the region around 1912 when the Longmont Aqueduct, which supplied water from Longmont Reservoir to the power plant, can still be viewed on the north side of Hall Ranch. The name Hall Ranch was first applied to the land in the early 1940s when Hallyn and June Hall purchased a chunk of the surrounding land. WILDLIFE: Hall Ranch is rich in wildlife. It is considered a crucial nesting habitat for numerous birds. Predatory birds such as golden eagles hunt here and are always on the lookout for a feast of prairie dog or squirrel. White tailed deer and rabbit are also commonly seen from the trail. One of the better places for observing wildlife at Hall Ranch is in the meadow at the junction of Bitterbrush and Nelson Loop. In addition to the cute and cuddly critters, don't forget that rattlesnakes love sunning themselves on the trail. Leave them alone, and they're usually pretty docile. GEOLOGY: The oldest rock in the area is about 1.7 billion years old and the youngest is approximately 62 million years old. The rocks are a mix of sandstone and granite.

21 days ago

Rock formations and soil color were beautiful. Not much shade.

1 month ago

Beautiful trail. Well maintained and well marked with benches placed along the trail. As other reviews mentioned as a hiker you constantly have to step off of the trail for MTBs.

2 months ago

It’s a very nice trail !!

mountain biking
2 months ago

Once again you can never tell what the rating system AllTrails uses.i would say the rating of moderate doesn’t seem to fit. I would rate the climb in to be difficult. The distance to be easy and the descent technically challenging. Morning rides are less packed and 5pm everyone and their brother/sister hits it after work. High traffic for sure on weekends and evening. I’ve seen lots of people carrying their bikes up hill and going ass over apple cart on the descent. Some may say it’s the line you take. There is some truth tho that.
I would tell my friends to ride it in the morning. that it’s lots of fun on the down hill and the climb is a challenge. It’s a trail short enough to do laps. Enjoy!!!

horseback riding
2 months ago

I absolutely love this trail. Wide open plains, trails around the foothills and narrow trails through the trees up into the mountains. Riding through the foothills of Lyons is just so beautiful. I heard watch for rattlesnakes on the rocks by the trails but haven’t see any. I love it here!
IMO horses need boots or shoes for sure through some of the really rocky areas. It’s mostly smooth sailing but I still wouldn’t go without them. Parking for trailers is an easy pull through.
GPS to the trailhead was off for me it was about a mile further up ahead on the right. Almost missed the turn into the trailhead. Because I thought I had past it. I pinned it for the next time. Watch out for trail closures on the website before heading out. Closes a lot because of muddy trails after a rain. Approx 9 miles. Happy Trails!

3 months ago

Great workout hike. Another one of my local favorites. The first time I did this trail I did the whole loop and did the hiker shuffle back to my car. I went up the nighthawk way and looped back down. Was a solid 9+ miles and I don’t even think I stopped. Oops. The views and scenery are amazing and I really liked the switch backs. Views are breathtaking.

5 months ago

This trail has a lot of people on it. It is great for bikers and runners.

7 months ago

3/13/18: Did this trail today w/my 9 y-o & 17 y-o. We parked in the lower lot but the upper lot has the bathrooms. We took the Nighthawk trail. No bikers allowed on this trail. The only issue we had was when the trailed forked off with no sign. The fork off to the right is what looks like a vehicle made path (what the path had been up to that point for awhile) and the fork to the left is a thin foot trail. We went right because it seemed to be going in the right direction. It wasn't the path but still got us to the same point - where you can take Button Rock trail or Nelson Loop. They need to put a sign at that fork! We took Nelson Loop to the right (east), stopped at the settlement then took Bitterbush trail to the parking lot. Almost as soon as we got on Nelson Loop the mountain bikes started coming. With the exception of the mountain bikes, our favorite part of the hike was Bitterbrush & Nelson Loop. If we do this one again we'll skip Nighthawk. It took us just over 4 hours to hike this. I don't think I'd brave this one in the summer. Not much shade. Must be really hot in the summer. We didn't think it was difficult but the kids complained that it was too long.

10 months ago

Maybe my favorite Boulder County open space. There are a lot of places where it feels more like plateau country than Front Range. Bike traffic is a big detractor for hikers on the Bitterbrush but it's often worth it due to the awesomeness. Especially love the rock garden area and it's fun to watch the more skilled bikers who can really ride it. A lot of the summer, this trail is a bit too hot. The mule deer here are not particularly afraid of people and especially when they have fawns and will often stand their ground when you meet them on the trail.

10 months ago

Wednesday, October 18, 2017

If you just want to hike this is not the trail you want to be on. There were so many mountain bikes. Too many to count, very frustrating.

Saturday, October 07, 2017

Nice hike on a beautiful Saturday. Arrived about 8:30 am to plenty of parking and didn't encounter much traffic on the way up, but friendly bikers thronged the trail both directions on the way down. Encountered a rattlesnake on the trail within sight of the parking lot, but it wouldn't budge, so I backtracked and took Nighthawk Trail the rest of the way. This is a good moderate hike for diversity in terrain and inclines, and it has some nice but not spectacular views. Take a brief detour to Sleepy Lion Trail at the top for some really beautiful views of Longs Peak and the Ralph Price Reservoir in Button Rock Preserve.

Sunday, September 17, 2017

Great easy hike with kiddos. Did it early to avoid the heat of July.

trail running
Sunday, June 11, 2017

Hall Ranch is fantastic for train running.

One error on the Wildlife section; the deer are mule deer, not whitetail.

Saturday, May 13, 2017

I go here often, especially in fall, winter and early spring. It's possible to hike from the main TH off Hwy. 7 west and connect with Buttonrock Preserve trails. I have seen lots of wild turkey on this trail. Watch for rattlesnakes in summer.

Tuesday, April 18, 2017

Good views and varying terrain. Lots of mountain bikers make it a little crowded for walking/running.

Monday, April 17, 2017

This is definitely one of my favorite trails! We saw mule deer, prairie dogs, lots of birds and heard a wild turkey (didn't see it unfortunately). There wasn't too many strenuous inclines but the sun is relentless so bring a hat and sunscreen. Beautiful views!

Wednesday, April 12, 2017

This is a fantastic hike/workout! The reviews that complained about bikes are incorrect, there is a huge portion of the trail Nighthawk, that bikes are NOT allowed!!!! I believe Bitterbrush is the one that allows bikes..
Always see lots of wildlife..highly recommend doing this trail and taking it all the way to Sleepy Lion/Button Rock trail.. about ten miles! Gorgeous snowy views at the top and Takes you to the pretty Longmont Reservoir and dam .. This is one of my favorite local trails...

Monday, March 13, 2017

Nice trail. Quite a bit of bike traffic. we caught it on a gorgeous day in February!

Tuesday, February 21, 2017

Great hike!!

Wednesday, February 15, 2017

Great hike- lots of different elements to this hike! Fantastic workout

Sunday, January 29, 2017

Great hike today (1/28). About 70% of the trail was covered with snow and ice, but you won't have a problem with good hiking shoes - no need of micro-spikes.

Friday, October 14, 2016

Definitely a moderate hike but a great workout. Good views here and there. Deer everywhere. Lots of bikers on Nelson. Overall though great hike.

Monday, September 26, 2016

Overall good hike on Nighthawk Trail. Sunny and very hot when I was there, but there was a few shady spots to escape the sun here and there. Great views of Long's Peak.

Sunday, September 11, 2016

enjoyed nighthawk trail. no bikes or dogs... a few horses and not crowded. nice view. not strenuous. then had a well earned lunch in Lyons

Saturday, September 10, 2016

Beautiful hike but a lot of bikes

Thursday, August 25, 2016

Obnoxious mountain bikers allowed. Don't bother hiking here. Same for most Boulder County open space. The bikers control it all. Sucks for hikers.

Wednesday, August 17, 2016

Great for mountain biking. Not as good for hiking. I prefer going hiking in this area at Heil Valley Ranch on US 36 close to Lyons.

Monday, June 27, 2016

Did the big 10 mile loop yesterday. It was so hot and there was no shade. The trail it's self was nice though:) next time I'll just go when it's cooler outside.

mountain biking
Sunday, June 05, 2016

Very nice trail to work on biking over rock features.

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