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Thunder Knob Trail

MODERATE 273 reviews

Thunder Knob Trail is a 3.3 mile heavily trafficked out and back trail located near Marblemount, Washington that features a lake and is rated as moderate. The trail offers a number of activity options and is best used from March until November. Dogs are also able to use this trail but must be kept on leash.

Distance: 3.3 miles Elevation Gain: 666 feet Route Type: Out & Back

dogs on leash

kid friendly

cross country skiing

hiking

nature trips

snowshoeing

bird watching

forest

lake

views

wild flowers

snow

Note: As of 2/20/19 - Users have reported that Highway 20/North Cascades Highway is closed due to winter conditions. Please check with the Ross Lake National Recreation Area before visiting. Note: As of May 2019, bridges at the beginning of the trail has been removed, so be prepared for a small clamber over a log to avoid creek water.

hiking
8 days ago

Trail head was easy to find and park at however it is a long a busy highway so take care in hiding your stuff out of view. The first crossing of the river was not easy to find a way to get over since they had already pulled the bridge. For the season. I made my way across on the way up and found a better way on the back way back. The trail was great all the way to the top and was very nice adventure.

hiking
16 days ago

The trail is bone dry as of 10/28. Your welcome. Also, awesome views 360. Peekaboo snow capped mountains throughout the hike too. Great short hike! Easy end of “moderate” for sure.

hiking
washed out
25 days ago

I would not recommend this trail at this time. It is basically a river. You’re welcome!!

hiking
1 month ago

Relatively easy hike with some nice views of the lake.

hiking
rocky
1 month ago

Went mid morning, it was beautiful! The creek to the trail head wasn’t bad, my dog enjoyed it there and back! The views at the end were amazing! I will be doing this trail again!

hiking
2 months ago

DIABLO lake

hiking
rocky
2 months ago

Water flowing at the start that needs to be walked through. We should have started earlier in the day. The trees are more sparse toward the top so was pretty hot. Had no problems with the dog.

hiking
2 months ago

Nice viewpoint, well marked, heavily trafficked due to camp ground at bottom. Also limited parking

hiking
rocky
2 months ago

hiking
rocky
2 months ago

hiking
blowdown
2 months ago

hiking
2 months ago

It was fine. Cute tail, but the view at the end was disappointing and mostly obscured by trees

hiking
2 months ago

This trail was absolutely beautiful. I recommend not doing it at the hottest part of the day. The views are so incredibly worth it.

hiking
bugs
3 months ago

Amazing views. Seriously amazing. Warning: there was a yellow jackets nest under the first set of double benches by a mountain overlook. The insects were territorial.

hiking
3 months ago

Spectacular views!!!

hiking
3 months ago

better options

hiking
3 months ago

An easy hike. There are quite a few patches of dead trees which isn’t pleasant to look at.

hiking
bugs
3 months ago

Nice leisure hike. Nice view up top. Worth the hike. Flies can get bad about 3/4 the way up. Hiked this around end of July , it was warm on the trail. Parts of the trail is open. But tolerable. Moderately trafficked. Get up there by 9 am and you’ll have a nice lookout and the trail to yourself.

hiking
3 months ago

Hiked 7/22. Trail is clear and dry. After the initial switchbacks, the woods thin out, so most of the upper portion of the trail is not shaded. Water is available in the campground at the trailhead. views of Diablo Lake and its stunning color are decent at the top.

hiking
bridge out
washed out
4 months ago

Footbridges have been removed for the season. The creek was overflowing due to recent rainfall, and during the hike, there was a torrential downpour that made the creek deeper and faster flowing when we returned. But the hike itself is beautiful and easy! Just be careful of it has been raining a lot.

hiking
4 months ago

Great trail for an easy yet scenic hike, views are memorable, as were the black bears I saw on the way down

hiking
4 months ago

Has a little loose rock on the trail and has quite a few switchbacks. View from the top is beautiful over looking Diablo Lake with mountains in the background.

hiking
4 months ago

Pretty solid hike with a fabulous emerald lake overlook waiting for you at the top.

hiking
4 months ago

Easy trail with a nice view of the lake overlooked by peaks

hiking
4 months ago

Lots of road noise, but it’s an easy walk up to a few different beautiful views of Diablo Lake. Easy access from the Colonial Creek campgrounds. Didn’t consider it much of a “hike” but a good outing if you’re feeling like you just need some low-level exercise for a bit. Trail was well maintained and not difficult at all.

hiking
4 months ago

Good easy trail

hiking
4 months ago

Good beginners trail. Some slight elevation gains but should be a nice relaxing hike for most with good views of Diablo lake at the end.

hiking
4 months ago

The view from above Diablo Lake was gorgeous. Even on a cloudy and overcast day you can still see how blue the lake is. Make sure you find your way to the water at the bottom of the trail.

hiking
4 months ago

Very easy enjoyable hike. There is a nice view of Diablo Lake at the top. Bathrooms and water access near the trailhead.

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