There's a lot of good ones in Oregon, but I'd have to say Cougar Reservoir. The fishing is typically poor, which is good for people like me who hate fishing and want to water ski/wakeboard all day It's a favorite of my family as you pretty much always have the whole lake to yourself and there's lots of places to explore on it. I also love the fact that there's no buildings at all within 30 minutes, no cell phone reception, no hookups for RVs...Cougar is REAL camping!
Blue lake trivia.... Used to be a privately owned park with a huge dance hall that burned down. Salmon used to spawn in blue lake and fairview lake as they were originally part of the sandy river delta... Along with the Columbia slough. That was before we started fucking around with the wetlands. Our family had a lot of picnics there too, and I remember the paddle boats, and the swim area with the concrete docks and big diving platform.
I've lived not far from Devil's Lake in Lincoln City for almost 50 years. Cool lake, but most of the accessible shoreline is private property, a little too urban for my tastes.
Why doesn't the government sell naming rights, to break the deficit? Joe's Fish & Grill Lake, Best Cod in the State
While I have plenty of lakes I have been to and camped at, my all time favorite is Fish Lake in the Rogue-Umpqua Divide Wilderness Area. Since it is a wilderness area, there are no roads to it. It is a backpacker's paradise in southern Oregon. The trail is a bit steap, but once you are up there, you have three lakes all to yourself. There is Fish lake, where I usually set up base camp, and then triangle lake and cliff lake all within a couple of miles. And, you are pretty much always alone in beautiful wilderness. Plus, In the fall, the area around fish lake has a tone of Matsutake mushrooms.....and they are delicious as fuck.
Definitely one of the most beautiful mountain lakes in the world. I'd also add Maroon Lake in Colorado and Swiftcurrent Lake in Glacier National Park to that list. In Oregon, my favorites are Lost Lake for the classic view of Mount Hood, Russell Lake for the view of Mount Jefferson, Crater Lake for the incredible shades of blue and Wallowa Lake. But, my all time favorite lake is a tiny little pond known as Gnome Tarn in the Enchantments in Central Washington near Leavenworth. On a calm morning in early October, when the larch needles are gold and back lit at sunrise, the reflection of Prusik Peak is sublime. BNM
I would also add Nambe Lake just outside of Santa Fe. It's a hell of a hike to get there, but it's so worth it.