Best Tent Camping near Sultan, WA

The Red Bridge campground is on the very scenic Mountain loop Rd in the Mount Baker-Snoqualmie National Forest. It's a very beautiful drive. Nestled in some great trees, there are 13 sites with shade, right along the river. The camp host was very nice and sold firewood on site. There are no hook ups, and no water spigots so be sure to plan accordingly. There are bear proof trash cans and vault toilets available. Each site has a tent pad, picnic table and fire ring. This campground provides ample hiking, fishing and I saw people kayaking plus its not far to a hike to some glacier caves! Also check out the old red trestle bridge just outside of the campground. At $15 a night you have to see this place. 
I highly recommend Red Bridge campground.

Great place to bring your LQ (any size rig) and camp with your horses. There are a few non-equestrians, but we need to keep this a place for equestrians because we are losing more and more campsites.  Trails are well maintained and extensive.

No water or electric at the camp, but you can drive down to a creek and pump or collect water for your horses. You will be boondocking.

High-line poles are available to high-tie your horses. We set up a portable corral and were fine. Picnic tables and fire rings are also available.

No manure pile or wheel barrow. There is a vault toilet and I got cell service on my phone.

Cooper Lake is absolutely stunning and admittedly the campsites are situated pretty well for views and privacy but there are definitely Pros and Cons to this campground.

Pros:

Right on the lake and if not you get a very private site walking distance to water
Great hiking trail

Lake access 24/7

Lot's of big shade trees

No internal combustion motors 

Vault toilets in good shape

Dumpsters

Cons: 

Extremely busy (and LOUD) day use area

Steep hill and trails to all the sites - pack light and even then it is A LOT of work getting into your site

$18 for a walk in site...? eh a little steep for me

Did I mention the loud day use area with lots of screaming kids?

No bear boxes by the lake so you also have to trek your cooler/dry goods up the hill every night to not attract wildlife.

All in All this was a solid 3.5 stars.  There were pros to out weight the cons but in the end if I am going to walk that far to haul my stuff into a site I want it to be pretty remote/serene OR be a little cheaper.

Every dispersed campground we checked along this road (maybe five or so) was littered with human feces and toilet paper everywhere. We found a literal bucket of human waste beside the river with a soiled pool noodle nearby I can only assume was being used as a toilet seat. Please, if you care about keeping nature wild, carry out your toilet paper and dig a cathole or use the outhouse in the campground. If you don’t know what a cathole is, you should probably should not being using dispersed camping and try the campground down the road. We ended up staying at the campground because we couldn’t find dispersed camping where there wasn’t poop and had a positive experience there. Leave no trace!! 

https://www.nps.gov/articles/leave-no-trace-seven-principles.htm

This campground is easy to find but a long drive into the woods on a bumpy gravel road. I made it in a Camery but it was a bumpy ride. Closest store is 45 minutes away so make sure you bring everything you need including firewood. It gets pretty chilly as the campground is well shaded. The river is very loud so you really don't hear your neighbors. The bugs are terrible, I've never seen mosquitos that aggressive. Each site had a tent pad, picnic table, and fire ring. There are some spots closer together but plenty that are set apart enough that you have privacy. Beautiful campground. No cell reception. One group had kids who were older but we didn't see any other kids. Well taken care of vault toilets though there was no host when we were there. Four stars only because the bugs were so bad, everything else about it was perfect for what we were looking for.

Camped August 8-11 2021 during a burn ban but it was still worth the escape from city life. Temperatures were within the 80s but during our last day, it was in the 90s. There are 2 vault toilets (one by the host area at Site 3 and one by campsite 10). Rented 3 campsites (10, 12, 13) and stayed on site 13 which was at the very end of the campground and I loved the privacy it had. Site 12 had direct river access which was awesome! Site 13 has a trail leading to it but somewhat steep. I would say that it was very clean and well kept. There's only a few mosquitoes but repellants would be ideal. The town is literally less than 10 minutes away in case you need some essentials. There is cellphone reception which is great if you prefer to camp and still be connected. As always, pack in pack out and leave no trace. The only downside is that it is by the road but good thing is there isn't much traffic come night time. Old Sauk Trailhead is about a mile away. You can get Geocaches too if you're into that. 

Missed the campground entrance but the turnaround is just there. Lots of campers seem to miss it the first time (including us). If you're at Site 13, you'll see the many vehicles that stop and turn which is hilarious.