
Gross Reservoir via Forsythe Canyon
Type … Hike, Woods Wander
Highlights … Waterfall, Lake, Creek
Seasons … Late Spring, Summer + Fall
Difficulty with Kids … Easy to Moderate due to a few short steep sections
Trail Details … All much as you want! (AllTrails)
Closest Town … Boulder
Shade … Plenty
Parking Situation … Plenty
Potty Situation … Pit toilets at trailhead
Stroller Friendly?… Nope
I love finding alternative hiking spots that don’t involve the i70 corridor, and this one checks all the boxes. Almost the entire path runs parallel to a creek giving kiddos plenty of opportunities to stop and splash, culminating in an awesome waterfall and then the reservoir.
This trail also provides a ton of shade along the way and has a kind of “FernGully” vibe. I love it for a Woods Wander because the whole trail is interesting for littles one so if you just make it to the creek, or the waterfall, or all the way to the reservoir, it’s going to be an awesome adventure.
TRAIL TIPS
Safety tip. If you do get to the waterfall, DO NOT SCALE DOWN THE FALLS. The AllTrails map is confusing here (and there is zero signage). We saw several groups going the wrong way down the falls and it looked scary af especially with kids in tow. If you dead-end into the waterfall, you’ve gone too far and need to back track to hit the trail again. The trail will take you up a steep section to the far left of the waterfall. This section is steep but very short.
Buggy at times. I’ve read that it can be buggy sometimes so pack the bug spray.
Bring water shoes for extra fun! There is a lot of water along this trail so I suggest bringing water shoes or a change of socks for littles. Be prepared for wet kids on this one!
Download your driving map. Pay attention to driving or download the GoogleMap as there are several turns to get to the trailhead and no service when you leave! We ended up in Boulder instead of Black Hawk because of this on our way back 🙂
GROSS RESERVOIR MAP
The trail gets wonky at the waterfall. The trail veers left (straight up) right before you reach the waterfall. If you’re standing on top of the waterfall looking down, you’ve gone too far.

The trail has definite woodsy, fairy vibes

The waterfall is impressive!

At the top of the falls

Mini waterfalls perfect for splashing

Water shoes were a win!

Stream that feeds the lake