To get to the Thomas Lake trailhead on Gifford Pinchot National Forest Road 65, drive to Carson, WA via I-84 and Bridge of the Gods or I-205 and WA 14, take Wind River Road (paved) up into the mountains, turn right onto Meadow Creek Road (paved) (signed "Sawtooth Berry Fields") and right again onto gravel Road 6507. Despite the signs, 6507 is fine for passenger cars unless you drive so fast you can't dodge the potholes. If, like me, you have a new car, the superfine dust on this road (gift from St. Helens) will amply disguise this fact from any trailhead thieves. Then left on Road 65; the trailhead parking lot is about 1/2 mile north, exactly 2 hours' drive from Troutdale.. NW Forest Pass required; our funds have paid for a shiny new toilet and a highly engineered trail (new bridges and raised causeways) as far as Thomas Lake. The Gifford Pinchot NF map is useless for road navigation here. South of Mt. St. Helens the main roads all have only names on the signs while the USFS map has only road numbers. The Benchmark Atlas of Washington is a far better road navigation guide and provides our good moderators with longitude/latitude--approximately 121:52�30"/46:00�00". For hiking I used the USFS Indian Heaven Wilderness map.
This place should be called Labrador Retriever Heaven! Most parties had at least one dog, and nearly all the dogs were Labs. The doggie high point (unless you were a human trying to filter water) was at Junction Lake Sunday noon when 10 dogs were romping together in the lake! They were having such fun that I overrode my firm belief in keeping dogs leashed and let my dog Hysson (Lab/Golden cross) join the crowd.
Here's Hysson on the highly engineered Thomas Lake trail: 
My plan was to follow the Indian Heaven Lakes Loop described at http://www.nwhiker.com/GPNFHike63.html I made a couple of changes to the suggested route. I took the northerly loop clockwise, camping at a pond between Bear and Elk Lakes the first night and at Junction Lake the second night. Sullivan's 1993 edition mentions an unmaintained trail that leads from near Blue Lake to Junction Lake, at some distance from but paralleling the Pacific Crest Trail. I found this trail well-used and easy to follow, leading through beautiful meadows (the PCT is mostly in forest, probably to protect the meadows from "Interstate 2000" traffic). Including this trail turns the partial loop into a figure 8 so that the only trail traversed twice is between Blue Lake and the trailhead. Along the Thomas Lake Trail towards Blue Lake, find a sign "Blue Lake 1/2 mi." and a visible path to the left. Here's the trail junction:
To find the northern end, go south on the PCT from the Lemei Lake trail junction, cross the (dry) outlet of Junction Lake, and find a sign "East Crater Trail 1/8 mi." Just past this sign is a distinct path to the right (as you hike south) in a small grassy meadow. Please, if you take this unofficial trail, respect the fragile meadows and stay on the path.
Of the lakes on this route, Bear, Elk, Deer and Clear Lakes, at the north end of the loop, are large, deep and very beautiful, as are Thomas and Blue Lakes at the southern end. Here's Clear Lake, mobbed as were most of the most "campable" lakes: 
Most of the other lakes were ponds which don't quite dry up in the summer. Shores and bottom are muddy, no doubt due to multiple contributions from Mt. St. Helens, which makes it difficult to get water from some of the lakes (such as Lemei) without sinking into the mud. Here's Junction Lake in a more peaceful (dogless) moment: 
Blue Lake has my vote as the prettiest of all the lakes 
but don't plan to camp there on a crowded weekend. The USFS has restricted camping to 9 designated sites in the entire Blue Lake area and 6 for the Thomas Lake area.. The result, of course, is that other lakes (like Rock, halfway between Blue and Thomas) get pounded down as well. Camping away from the crowds at the lakes (which I�d have preferred) is difficult because in late summer the only water is in the lakes, the meadows are very fragile with thick heather and huckleberry near the trees, and the forest floor is uniformly covered with thick brush, mostly huckleberry--no space for even a small tent..
The mosquitoes that chased earlier hikers out ahead of schedule were absent. Huckleberries were pretty thin, often only 1-2 berries per bush. I picked enough to garnish dinner and breakfast each day, but the two quart Nalgene bottles in Hysson's doggie pack remained empty as we went out. The best picking I found was near Junction Lake. A family I met said picking was also good near the Racetrack. The only large wildlife I saw was the deer I just missed on Highway 14. Lots of fresh elk tracks, but no visible elk, not suprising with the hordes of people and dogs.
The weather was excellent. The east wind (not nearly as hot as at home) kept things pleasant Saturday and much of Sunday. Sunday night I dreamed that people were picking berries behind my camp and shining flashlights on my tent and then awoke to lightning! A puny storm by Rocky Mountain standards, but potentially serious because there were only a few sprinkles of rain. The ranger I met writing tickets at the trailhead Monday afternoon said that no fires had been called in yet but they were keeping a close lookout.
As a recent convert to lightweight backpacking, I confess to being amused at the size of some of the packs carried. I don�t include parents acting as Sherpas for their young children, who are making a commendable sacrifice to let their children enjoy backpacking.. The most extreme was a party of 6 people, 3 of them carrying enormous packs, leading 3 horses, also well loaded down. When you figure 150 lbs. times 2 horses (the 3rd horse would carry horse equipment and feed), plus three 50 lb. human packs, that's a lot of stuff for a weekend!
Indian Heaven is a marvelous place to take children backpacking; I met many families with children who were having a wonderful time (almost as many kids as dogs!). Hysson and I had a nice relaxing weekend leisurely strolling through forests and meadows, grazing on the occasional berry and sampling lakes, which is what we intended, although I could have eaten lots more berries. But unless you like hordes of people and Labs and competition for camp spaces, you might want to avoid the area on Labor Day weekend. With huckleberry bushes everywhere, a few already starting to turn red, the colors should be extraordinary in a few weeks, and the elk will soon start bugling.
