Set aside a weekend for this hiking excursion, because once you get to the lake, you won't be in a hurry to leave. Just over the ridge from Lake Dorothy, Snoqualmie Lake offers ideal lakeside camping, fishing and plenty of solitude. The 13 miles are manageable as a day hike, but don't be fooled by the net elevation gain of 950 feet. One must hike over a ridge to get from Dorothy to Snoqualmie, so the total gain ends up being over 2,600 feet round trip.
Start out hiking the trail to Lake Dorothy, crossing over Camp Robber Creek and skirting the 2-mile lake shore until the trail reaches an inlet on the south end. There is no bridge, but there are plenty of rocks to get you across to where the trail continues on the other side and soon begins switchbacking up the ridge. The trail is steep and a bit rough, passing under towering firs and cedars and through dense patches of wild blueberries. Stop for a berry snack and have a look back down the ridge for fleeting views of Lake Dorothy below.
Once over the ridge, hike past Bear and Deer Lakes and ascend another ridge for your first view of Snoqualmie Lake far below. Navigating the rocky switchbacks down to the lake takes some effort, but you will be pleasantly distracted by red columbines, more blueberries and encouraging glimpses of the lake as you go. At the lake, you will come across several campsites; one particularly inviting one sits right off a sandy beach near a large, flat lunch rock. Set up camp, lounge in the sun, take a dip in the water, or try your hand at catching fresh trout for dinner.