I did a loop backpack trip over 4 1/2 days: Deer Park, Badger Valley, Cameron Basin, Dosewallips, Gray Wolf River, Deer Park.

Overall - a great loop for 4 1/2 days. (3 days would have been ok but would make for long days and 4 days would have been plenty but I had extra time).  Lots of up and down and variety, from the initial ridge hike with sweeping views, to lush/brushy valley hikes, carpeted trails in old growth, swimmable lakes and alpine/rocky valleys and passes. Bonus with the ripe huckleberries and blueberries (and a few thimbleberries).

Notes and details:

• Day 1 - Deer park campground trailhead to Badger valley (via Elk creek trail) before Obstruction point - 11.7 miles, 2,900 ft elev gain, 6 1/2 hours
  • More up and down than I expected along the ridge, but great views. Water unavailable until about 1/2 mile down from the ridge. Some up and down through the valley on decent tread (with some roots/rocks). Swam in Grand Lake and Moose Lake. Preferred Moose lake for the camping (nice sites next to lakes) and swimming (clearer water/less algae). Wildfire smoke and haze during the day.
• Day 2 - Badger Valley (Moose Lake camp) over Grand Pass to Upper Cameron Basin camp - 6.7 miles, 2,651 ft elev gain, 5 hours
  • Great views going up and over the pass via switchbacks and easy to follow trail. (I slipped on a loose rock and pulled my hamstring after the pass, so the rest of the hike was a challenge and slowed me down). More short, steepish uphill (and some brushy) sections on the way to Upper Cameron than I expected. A few decent campsites below and above the waterfall. (no signage and no pit toilet). Worsened smoke and haze until late in the evening.
• Day 3 - Upper Cameron basin over Cameron and Lost Passes to Bear Camp - 5.8 miles, 1,193 ft elev gain, 4 hours
  • Another pass with some steep switchback sections on small scree (I was glad I was going up and not down - it wasn't too slippery but I didn't want to fall again). After the long up and down from Cameron pass, getting over Lost pass seemed easy (gradual elevation gain through meadows). A long descent to Dosewallips and easy gradual trail (with some brushy sections) down to Bear Camp. (Two nice campsites across the creek). Toilet available.
• Day 4 - Bear Camp down Dosewallips and over Gray Wolf pass to Falls camp - 10 miles, 2,646 ft elev gain, 7 hours 
  • Easy, brushy trail (with huckleberries) down to the turnoff for Gray Wolf pass. Kind of slog going up many switchbacks in the woods to get to Gray Wolf pass. I took a nice swim in the little lake on the left about 1/2 mile down over the pass. More brushy trail from the pass to Falls camp, which has one decent campsite next to the trail and two up next to the meadow. (no toilet). 
• Day 5 - Falls camp to Deer Park trailhead - 10.49 miles, 3,252 elev. gain, 5 hours. 
  • Nice spongy tread through old growth along the Gray River made for easy going until the long switchback on smooth tread on Three Forks trail up to Deer Park.  (limited water on that trail). Ellis and Gray Wolf Camps looked nicer than Falls camp so next time I might stay at either of those instead). It was great to go from dense fog in the valley to bright blue skies at the pass.

A four-person Gray Wolf trail crew spent Labor Day week removing fallen trees from its namesake trail in addition to clearing the Three Forks trail down from the Deer Park campground.  The Gray Wolf trail is now free of fallen trees from the Olympic Forest / Park boundary up to Falls Camp.  Later this month, another crew will head in to clear the trail from the Slab Camp bridge to the ONF/ONP boundary.

Accessing the trails at the ONP Deer Park campground was easy.  The road, while steep and narrow, was in good condition albeit with some washboarding on the steeper curves.  Smoke from the Bear Gulch fire was only noticeable on the last day in and primarily at the higher elevations.  The Three Forks and Gray Wolf campsites were comfortable due to the river's cooling influence; both have newer privies in good condition.

Day 1 - Drove to Deer Park Campground. Road was washboarded in places and pretty dusty. Many pull outs for allowing others to pass. We arrived later in the afternoon than planned, and almost every parking spot was full, but we found a spot, and still had time to hike down to Gray Wolf Camp and set up for the night.

Day 2 - Hiked from Gray Wolf Camp to Falls Camp. This trail was in good shape with several beautiful log bridges to cross the creeks. Falls camp had no visible signs, no established privy, and downed trees over much of the lower half of the area. We turned right off the main trail at the gravel bar and found a large campsite up the trail on the left hand side of the meadow. There were many people camping in the area along the main trail.

Day 3 - Hiked from Falls Camp over Gray Wolf Pass, down to the Dosewallips River Trail, and up to Dose Meadows. The trail from Falls Camp up to the pass was overgrown in several places and we had to use our trekking poles to navigate a couple thickets of Devils Club. As we climbed higher, the trail cleared out and opened up to sub-alpine meadows and bigger vistas. We encountered several other hikers at Gray Wolf Pass, stopped for a snack, then enjoyed a downhill stroll through wildflower meadows to the Dose River Trail. At this trail junction, the bugs were the worst we encountered on our entire trip. We arrived to Dose Meadows and found other hikers watching a large marmot sprawled out on a large rock in the sun. The campsites along the river's edge were all occupied, and we were wary of rain, so we set up camp under a large tree to the left of the meadow. Several other parties arrived after we did, but there were plenty of decent places to make camp.

Day 4 - We got up and began the climb up the Cameron Pass Trail over Lost Pass and on over Cameron Pass. The guidebook describes the first part of this trail as "insanely steep," so we were prepared for the worst, but the trail wasn't as bad as we expected. Before long, we reached Lost Pass and panoramic views. From Lost Pass to Cameron Pass, the trail drops a bit before the long climb up to Cameron Pass. Views are great and the trail is more moderate than the section from Dose to Lost Pass. After lunching at Cameron Pass, we proceeded down the Cameron Creek Trail. This trail was snow free and had fairly good footing all the way down to the upper valley floor. After we passed the Upper Cameron Camp area, the trail got brushy and tight in several places. We reached the junction with the Grand Pass Trail and were excited for a short hike down to Lower Cameron Camp. Unfortunately, our Green Trails map showed Lower Cameron Camp at the location of the remains of an old shelter. We searched a bit, but we could not locate the actual camp, so we double checked the guidebook, and it said that Lower Cameron Camp was 0.4 miles further down the trail. It felt like we hiked much further than that, but we eventually found a clear trail to a nice creek-side camp with spaces for 2-3 small groups.

Day 5 - Hiked down the Cameron Creek Trail through beautiful old growth forest along the creek until we reached the junction back at Three Forks. We opted for a short day by camping at Three Forks. There were a few campsites along the creek down the trail from the shelter and privy. We picked a spot by the creek and rested up for the climb back up to Deer Park CG. It looked like the campsite trail continued on down the creek, but it was covered in downed limbs.

Day 6 - We woke early, broke camp, and started up the trail to Deer Park CG. Heading back up this trail was easier than we expected, but our packs were lighter and we had several days of conditioning under our belts. It was fun to look back and see several of the places we had hiked off in the distance we we reached the top. 

This is a great loop for experienced backpackers. We covered 43 miles and 11,483 feet of elevation over our 6 day trip. If you travel light and fast, you could easily complete the circuit in 4 days (by combining Days 1 and 2 and Days 5 and 6). Beware: In several places, the brush hanging over the trail conceals large marmot holes, creek crossings, and other hazards. Watch your footing as you go. 

We spent six days backpacking the Northeast Olympics - Grand Valley Loop through Olympic National Park, starting from the Deer Park Trailhead and moving clockwise along the Gray Wolf River, over Gray Wolf Pass, down the Dosewallips River, up Lost and Cameron Passes, Grand Pass, and then back to Deer Park via Obstruction Point.

Camps were mostly scenic and uncrowded. We camped at Gray Wolf (new privy, spacious, beautiful forested site), Falls Camp (found a nice camp a short way up the Cedar Lake trail), Dose Meadows, Upper Cameron (peaceful and wildly scenic creekside camp in Upper Cameron basin), and Grand Lake. Mosquitoes were never horrible, but worst at Upper Cameron (recent snow melt). Flies were pesky, especially a few horseflies on the passes.

We explored several historic sites—remains of old shelters, bridge timbers, nails, and even found insulators from past ranger infrastructure. Wildlife was active: deer wandered through camp almost nightly, one trying to steal my hat at Upper Cameron, a marten startled us, saw one marmot but heard many more, and fish were jumping in alpine lakes. No bears were sighted.

Trails ranged from mellow forest walks to steep climbs and rocky passes, including narrow paths at Gray Wolf and Cameron passes and a sketchy traverse of a gully coming down from Cameron pass. No snow on the trails!

The final day offered spectacular ridge views before we descended to Deer Park and ended the trip with an unexpected treat—ranger Donovan invited us into his historic cabin, filled with relics and stories from the park’s past.

A great mix of scenery, solitude, and Olympic history.

We hiked the Grand Valley - Cameron Creek Loop, counterclockwise, in 3 days / 2 nights. Roughly:
Friday: ~ 5mi from Deer Park to Roaring Winds
Saturday: ~13mi from Roaring Winds to Lower Cameron
Sunday: ~9mi from Lower Cameron back to Deer Park

For anyone route-planning: I’d suggest considering an out-and-back from Deer Park to Grand Pass via Obstruction Peak rather than a loop, and would suggest skipping Grand Pass to Deer Park via Lower Cameron. More details down below.

Deer Park to Obstruction Peak: Gorgeous mountain views to the south with some early peek-a-boo views of the Strait of Juan de Fuca and BC! There are a couple very steep climbs, especially closer to Deer Park, and most of the route is fairly exposed. A good portion of the route has a steep drop to one side, but the trail is in great condition and plenty wide. We’d heard there can be snow on trail late in the season — by this weekend, there was nothing.

Obstruction Peak to Grand Pass: Incredible mountain views followed by gorgeous lakes and meadows. Super fun, pleasantly strenuous ascent to Grand Pass.

Grand Pass to Deer Park via Lower Cameron: Didn’t love the rest of the hike. First, you drop 2400’ in 1.6mi. This was SLOW going for us, with some early portions on pretty steep shale. After you make it through this descent, you walk along the river for ~7mi, with some ups and downs and ~2000’ total gradual descent. This walk is absolutely a pleasant river valley, especially the portions further to the east, but after the show-stopping views above it felt a little underwhelming. We’d heard that the river trail was unmaintained but that was not our experience - it was perhaps the slightest bit overgrown but totally followable and very few blowdowns. We heard from a park volunteer that last year they maintained this portion of the trail, but prior to that it hadn’t been maintained for a decade. Anyway, I’d say the trail gets prettier the closer you get to Three Forks camp, which looked like a beautiful place to camp. Finally, after Three Forks, a 3200’ climb in ~4mi back up to Deer Park. The climb is graded well and generally shaded, with no views until the last quarter or so. All-in-all, a fine option for making a loop but…. who needs a loop when your backtrack option is spectacularly gorgeous?

Camp 1: Roaring Winds. No roaring winds for us - a peaceful camp with incredible views. Dry camp - bring water. See below notes on water for more.

Camp 2: Lower Cameron. Camp doesn’t exist where it’s mapped on AllTrails or Gaia. There is one site a bit further to the west, which was taken by a nice group when we arrived. We found an alternative campsite.

Water: No water between Deer Park and Obstruction Point, nor water at either trailhead. Plan accordingly! After Obstruction Point, there are some lakes a few miles down. Some good creeks between Grand Pass and Cameron Creek, and then many of the seasonal flows marked on AllTrails that feed Cameron Creek weren’t running this weekend. The inflow running near Lower Cameron was running.

Snow: none on trail the whole way.

Bugs: minor nuisance, but handleable with bug spray.

Road to Deer Park: great condition though along the side of a mountain so a dropoff on the right side ascending. No issues with my VW Golf so probably fine for anyone.