WHEN THE temperature in Washington hung in the 90s for 24 of 26 midsummer days, Ann Lordeman decided she'd had enough. She needed to find cooler breeze.

Her solution was to head - of all directions - south. Destination: Great Smoky Mountains National Park on the North Carolina-Tennessee border. She and her party had never been there before, but with careful planning they hoped to find cool, quiet, unpolluted and uncrowded evenings among the 6,000-foot-plus peaks where they would hike for four days.

The key was to find a remote section of the park - national parks tend to be crowded these days. A good beginning wa to steer clear of the tourist trips around Gatlinburg, Tenn., Waynesville, N.C., and the Cherokee Indian Touring Guide showed other concentrations of campgrounds, motels and restaurants.

"Give them a wide berth, too," Lordeman decided. "That's where everyone else will be."

The Sierra Club described numerous circuit hikes into remote sections of the park. But even the Sierra Club guide sounded like a Chamber of Commerce brochure: trout lurking in deep clear pools, cascading waterfalls, varieties of bird life and no people.

Pristine. "But will it really be that way?" she wondered aloud as she turned onto the Blue Ridge Parkway.

The 500-mile drive dow the Blue Ridge was enlivened by several short hikes to waterfalls and magnificent views.

Ashville, N.C., is near the end of the Parkway and on the doorstop of the Smoky Mountains. It wa s the logical place to narrow the choice among the many hikes that sounded remote. The manager of one of the local backpacking stores pointed out the least used areas of the park and the Plumlea Angler, the best fly fishing shop in the area, recommended several trout streams.

From the many trips described in the Sierra Club guide, three that offered wilderness, native trout fishing, spectacular scenery and something less than grueling paths stood out.

Back country camping permits are required, so on the theory that crowded ranger stations offer the least information, the last stop was at one of one of the more out of the way stations.

But it was the nearby stream that convinced the campers that they had found their hike. The stream was loaded wit wild rainbow trout. For eight miles it paralled the footpath. Every 100 yards was a pool deep enough to swin and every 20 yards was a clear pool packed with wild rainbow trout.

Carolina slate-colored juncos, red crossbills and thrushes skittered back and forth from the rhododendrons to stream's edge and the waterfalls really did cascade Pristine.

"The Smokies are covered with blackbears," the ranger advised. "You can expect to see them in the park country but they are harmless if you give them a wide berth." Among other things, that means carry 60 feet of rope to hang your food at least eight feet off the ground and at least four feet from the nearest tree. Bears want your food, so you should not take your pack or even clothes that have food odors on them into your tent.

"We had one airborne bear last year," the ranger continued. "Awful smart. He'd climb the nearest tree, get a few feet above the suspended pack of food and then leap for it. He learned that either the branch or the rope would break.

"We had to transport him out of there, he nailed so many packs. He only weighed 250 pounds, but he had the longest, glossiest coat I've ever seen, probably on account of all the peanut butter sandwiches and dried fruits he ate."

One beauty about wilderness hiking in the Smokies is that you walk all day and see no one until you reach the next designated shelter or camping area. It is a perfect mixture of solitude and company when you want each. A campfire with food and story-swapping is a lot better than being alone with the dying embers of a fire.

The first night Lordeman was visited by a smaller bear. In an apparently curious mood he ambled around the camping area until a fellow hiker with a police whistled scared him off. Noise is always a good idea when dealing with bears. Their eyesight is poor and it's best to let them know you are around so that they don't ever feed cornered.

The shelters in the Smokies are bearproof. The side that is ordinarily open is sealing with a wire fence and locking gate. The security is deceptive - bears don't get in but the field mice do. You notice it if a bear walks into camp, zeroes in on your pack and thinks "dinner," but an aggressive field mouse is every bit as formidable.

One got half way through Lordeman deman's "gorp" - a high-energy trail food mixture of raisins, M&Ms, and peanuts - before she noticed the the rustling in her pack.

Mice will steal you blind and then walk right across your table to get to your dinner. You should hang your packs inside the shelter and run the rope through an inverted empty can or clamp a mess kit to the rope to keep them from reaching the packs. It's also more appealing to sleep with your head away from the wall so the mice will run across your feet and not your face.

After four days, Lordeman was convinced the Smokies are great for serious wilderness seekers if they read the guidebooks, consult the outdoor shops, and by all means talk to the rangers. There's so much there for those willing to do the work to make it a private experience."