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Print Friendly MapThe John Dellenback Trail circles the sapphire blue Diamond Lake in south-central Oregon, only about 20 miles north of the state's more famous Crater Lake. The paved pathway connects the campgrounds that ring the shoreline and provides magnificent views of snow-covered Mt. Thielsen and Mt. Bailey. The lake's South Shore Picnic Area offers a nice resting spot to take in the views and enjoy a packed lunch.
For more outdoor adventure, the lake—nestled within Umpqua National Forest—is popular for fishing and boating; hiking and equestrian trails also crisscross the area. In winter, the waterfront trail can be used for cross-country skiing, snowshoeing, and mushing.
Parking lots can be found all around Diamond Lake; clockwise from the north end of the lake, you'll find them at: Diamond Lake Campground (east side of the lake), South Shore Picnic Area, Broken Arrow Campground (south side of the lake), and Thielsen View Campground (west side of the lake).
Just road the loop at Diamond lake and trees have been removed. Path is still damaged where one trees roots lifted up the asphalt but still passable. Trail is littered in pine needles but still safe to ride with your kids. A definite 5 star review once the cleanup is finished.
I rode this trail on 6/11/2025 with my family of four (kids 7 and 10) after spending the night at the Diamond Lake Resort Motel. This trail looked like it would be worth the detour on our family road trip, but apparently we got there too early in the season. There were literally HUNDREDS of trees down across the trail, including large sections of trail destroyed as root structures took the asphalt with it when trees came down. Is that normal every season or was 24/25 a particularly stormy Winter?
We started at the Diamond Lake Resort and rode counter clockwise. After 3.7 miles, we counted 35 times we had to stop and lift bikes over logs ranging from enormous to small-ish. We finally hit a cluster of trees across the trail so huge, we finally gave up and rode on the street, which was clear and lightly trafficked. Several times we attempted to rejoin the trail where it crossed the roadway, but along the southwest side of the lake we encountered huge snow drifts that hadn't melted yet. Keep in mind it was shorts and tank top weather, so the snow surprised us. Sadly, the tree situation never improved, except for the sections of the route that passed through the campgrounds.
Also, the mosquito swarms were the most intense I've experienced outside Alaska. We could not stop riding without getting utterly wrecked, and this was in the middle of the day with a comfortable breeze blowing.; they were large and hungry. This trail has wonderful potential and the area is very beautiful, but call the Umpqua National Forest Ranger Station first and get updates before you commit to this one. This trail should not have even been open until crews had completed clearing it. There was no signage informing of the conditions and that would've made all the difference. The Nat'l Forest really dropped the ball by not having the trail cleared this late in the year and by not having any warning signs of the conditions ahead.
We tried this trail but snow and trees still blocked the path. Hopefully, we’ll come back another day.
Very well worth the time and energy. Would do it again if I get the chance.
This trail had one wow moment after another with stretches right on the water, meadows full of wildflowers, and portions in the woods away from the water. It was biking through the wooded section that we came across a bear crossing the trail. Luckily, it was as startled as we were and ran quickly up the hill from us. We made more noise for the remainder of the ride. The trail looks to be well maintained with the exception of the painted markers where it enters campground loops and parking lots. Those needed refreshing as they were hard to locate in places.
The scenery was gorgeous! The rolling hill trail surface was in fair condition with minor root heaving and cracking . Work has started on the west side of the lake to correct these things. In several areas, the trail was covered with pine needles and twigs. There are many campgrounds all around the lake which have restrooms and water. There is a small store at the resort on the north end of the lake.
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