Gabrielino Trail: Jet Propulsion Laboratory to the USFS Dam

MODERATE 149 reviews
#49 of 223 trails in

Gabrielino Trail: Jet Propulsion Laboratory to the USFS Dam is a 8.2 mile out and back trail located near Pasadena, California that features a great forest setting. The trail is rated as moderate and offers a number of activity options. Dogs and horses are also able to use this trail.

Distance: 8.2 miles Elevation Gain: 639 feet Route Type: Out & Back

dog friendly



horseback riding

mountain biking

nature trips




partially paved


A multi-use trail that encompasses many different types of terrain. The trail is paved to begin, but eventually changes to more natural surfaces including sand, rocks, boulders and dirt. There are several campsites and picnic areas along the way.

7 days ago

turned off 1\2 4.2 hike

23 days ago

Fun, scenic, and non-strenuous day hike, great for families and dogs. Beautiful canyon views and shaded throughout—have done this hike in the height of summer without issue. Would rate this as easy, although the total distance and stream crossings might make it a little difficult with small children. Vault toilets at the Gould Mesa campground, but no potable water so bring enough for the entire 8.5. Great hike to try out trail running on, as the trail is consistently well-maintained and fairly even. Watch out for bikers and the occasional poison oak.

24 days ago

Did not go to Switzer. Just did the Arroyo trail. No dust, No bugs. Lots of bikers though, they were very friendly. Definitely coming back with a bike. Water crossings were easy and water levels were low. It does get cold if you stay past sundown so bring layers, lights, plenty of water and snacks.

mountain biking
3 months ago

2nd ride with flat pedals - went ok. My feet would lose touch with pedals on jumps - need to work on my form. Bigger issue - rear suspension is way too soft. Need to adjust - I’m getting lots and lots of pedal strikes.

4 months ago

Significant paved portion (1mi) with interspersed shade, then it gets fun. However it's super busy. too busy for me. bikes. dogs off leash. not a great time for someone with a dog and toddler in tow.

mountain biking
4 months ago

With Kevin Lin

Starts off nice and gentle on a paved road for about a mile, then it’ll transition to a sand/gravel road. There’s a water fountain right by the doggie pool marked on this map, take full advantage as it is your only one. Use this water for drinking as the many streams can be used to refresh yourself. I recommend a change of shoes and socks for the end as you will most likely get wet but the water is amazingly refreshing. Roads can get a bit narrow and will have rocky parts but nothing extreme. Very nice as a starter hike with a bit of flavor haha. This should go without saying but always be aware of your surroundings and the road. Snakes, lizards, birds, and other creatures live here and we are visitors in their home so we should observe and not disturb :) have a great hike ladies and gentleman!

mountain biking
4 months ago

Rode solo - took photos of each stream. Slow relaxed ride.

Very hot. It’s actually 8.6 miles. Not 8.2. Watch out for snakes. We saw three

8 months ago

beautiful trail with many water crossing

9 months ago

Starts with a 1 mile stretch of paved road which transitions smoothly onto a shaded trail, which stays nice and cool on sunny mornings. The streams are flowing so there are several water crossings. We initially crossed streams via makeshift bridges of trees and rocks, but eventually ran right through the water which was never deeper that calf height. The water is very refreshing. Best part, everything looks so green and the wildflowers are blooming. No issues with traffic. Everyone sharing the trail was polite and friendly. It’s a great time of year to hike/run/bike this trail!

Sat Jan 19 2019

Too many mountain bikers flying through narrow trail areas! Not great! The first mile is paved & wide but the deeper u go the more crazy it gets, especially when mountain bikers come at u without warning. Not all of them. Some have bells which I appreciate but some just come down around a blind curve & it’s up to u to get out of the way or else! There are curvy narrow parts of the trail that seem extremely dangerous with all of that going on. I saw some people with kids & I thought... “No Way!”

Sun Dec 23 2018

Hiked this trail today 12/23/18. Very easy and beautiful with light traffic with friendly and courteous mountain bikers and trail runners. Tried my best not to get my feet wet but no luck ha! The waterfall way flowing pretty good at the dam.

Wed Nov 28 2018

this was a relatively easy hike not a lot of elevation change and some interesting structures on the way up there and we came to Brown Mountain Dam and there was still quite a bit of water saw a couple of salamanders also overall a nice hike

Sun Nov 11 2018

This is a very nice, easy hike with picturesque scenery. Don't be discouraged by the stretch of paved road leading to a more natural, multi-terrain trail featuring sand, decomposed granite, dirt, rocks, boulders, California coastal vegetation and many easy stream crossings along the length of the hike to the USFS dam. There is a nearly unnoticeable incline to the dam. AllTrails reports an 8.2 mi round-trip hike to the dam and back, but my GPS recorded 4.8 mi to the dam (9.6 mi total), with short excursions off the trail for pictures and to allow the dog to play in the stream). The trail forks off several times and offers picnic areas and a couple walk-in campgrounds. There is a small parking lot adjacent to a residential neighborhood that was full at 6:30AM, but street parking in the neighborhood appears to be allowed, at least on weekends. Very shaded early in the morning with longer stretches of open sun late morning heading back to the trailhead. There were very few hikers and bikers early in the morning. Heading back, around 9:00AM, the number of trail users probably tripled--bikers, hikers, runners, USFS on horseback.

mountain biking
Sat Oct 13 2018


Wed Jun 13 2018

Great hike but even funner bike ride! Lots of incline, streams, rocky terrain, bring water bx it can get hot. Half sun half shade and some “permanent campers” up top so be aware.

Fri Apr 20 2018

Old favorite.

Mon Feb 05 2018

This trail has a little bit of everything. I didn't go all the way out - about 5.5 miles out before heading back - but I am really, really glad I did this hike. The terrain goes from paved to tamped dirt to loose, deep, silty sand, to very rocky, to very wet. I am definitely glad I wore my Danners because they kept my feet dry even when my feet were partially submerged. A few of the stream crossings were no biggie - logs the whole way across. But this time of year even the crossings which only have large rocks to step across on are pretty tame. I went out early - started right before sunrise - so most of the hikers/bikers/dogs I saw were encountered on the way back. Lots of runners, also. If you hit this trail before 7 you will have a pretty quiet time. There are several campgrounds & picnic areas along the way. The second campground (the first one within the bounds of the Natl. Forest land) seems to be in need of more frequent visits by the rangers. The dumpsters were overflowing with trash, which doesn't seem very good for the wildlife, and it's an eyesore to boot. I would say this is an easy walk for the first 5 miles or so, save for the streams. This trail doesn't become truly moderate until the first incline. I will be back next weekend with my stepson. The first few miles are great for even little kids!

Mon Jan 29 2018

We hiked this trail all the way to the dam. Took us about 3 1/2 hours with no stops. It was a great trail. Stream water was low but still high enough to have to jump on rocks to get across. Eventually shoes just end up getting wet. Recommend bringing an extra set of shoes and socks to have in the car when you get back. Lots of bikers, runners. People hiking and dogs. Most off leash but it was fine. Trail was moderately busy until the camp. Looks like most people don’t continue after the camp to the remaining 2 miles to the dam. There’s a bathroom half way at the camp if you need it. Overall it was a great hike.

Sun Jan 07 2018

This is a beautiful trail, and great for trail running, as it’s a gradual climb, and then a quick return downhill. Plenty of people, but not too many on a Sunday morning to make it crowded. Be sure to hit it before the rainy season, because you cross the creek about ten times and if the water was any higher you wouldn’t get very far! This is also one way to get to a couple of camping spots that looked nice, under the trees and near the creek. The only reason I wouldn’t give this 5 stars is because there’s no view.

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