"When the falls are falling on you it feels so. . . excellent," says a little girl.

We pause on a rocky plateau about half way up Maryland's Cunningham Falls, which fall a total of 78 feet but do it in 220 feet of cascades, flumes, winding whitewater courses, babbling streams and inviting pools. We're going the opposite way of the water on a climb where getting there is more than half the fun. You can climb all the way up on dry rocks, but it's a rare hiker who can resist the pleasures of getting wet. Clambering over the rocks, you can be at the top in 10 minutes -- if you don't stop to rest in every pool or stick your face in every cool, crystal spout.

A huge rock hangs above us, and the water takes various routes, around, over and under it. To the side of the main routes, in deep shade, a rivulet flows swiftly but gently down a mossy slide. We flow with it, sliding down about 10 feet then braking with the sneaker-heels-in-a-crag method. We could do this all day, but roars and gurgles above us promise other pleasures.

We come to another plateau where a dozen streams converge, and we manage to walk through all of them; somebody's Labrador retriever joins us in the water, wagging his tail as he scampers out again. Above us, twin falls cascade into a pool, then split again. The mainstream falls in a flat, broad sheet over a cliff. An offshoot pours out faucet- fashion between thick clumps of moss. To climb higher, we have to push ourselves up on a felled tree, then find footholds on wet, slippery rocks. (Here my notes get a bit soggy.) There's an easy way around, through the hemlock and fern woods, but this is unthinkable now. We're committed to the water route.

The steep spot conquered, we're rewarded with a wide expanse of flat, lichen-splattered rock that we immediately christen "the beach." Here's the sort of green glade Corot painted, the dappled sunlight Gerard Manley Hopkins wrote poetry to, the crystalline pools the White Rock folks made commercials about. We take sandwiches out of a backpack and fill plastic wine glasses with water from a natural spigot.

After lunch, we bathe in a long, narrow lagoon of a pool, plunging in at the top and floating about 20 feet downstream, then climbing out and repeating the process. The water is cold, but the rocks are warm. We have brought no towels, so the children warm up in still, shallow pools heated by the sun. Butterflies flit by, and the afternoon wanes. We want to linger, but there's a primeval urge to be at the top. We follow the water through the woods, over a carpet of hemlock needles and mushroom spores. When the water's roar softens to a gurgle, we pronounce this point to be the top and head down again.

On the downward journey, we relive the pleasures of the climb up and discover still more pools to splash in. We're more daring now, and even consider sliding down one of the steeper cascades. But when we ask a man who's sitting at the bottom of the cascade if he slid all the way down, his negative reply is accompanied by such vehemence that we come to our senses. But in the bottom pool, the swimming hole created by the final cascade, there's no holding back. We jump off a rock into about five feet of water and swim over to stick our faces into the waterfall. Just below the waterline is a rock made smooth by generations of derrieres. We take turns sitting on it, letting the falls fall right over us.

My seven-year-old looks up at the falls we have just climbed up, down and in and, with the skepticism of a generation for whom reality is defined by theme parks, asks: "Is this real?"

Disney himself couldn't have built it better, dear.

FINDING THE FALLS Cunningham Falls fall in Cunningham Falls State Park near Thurmont, Maryland. From the Beltway, take I-270 to Frederick, then continue north on U.S. 15. In Thurmont, take Maryland Route 77 west. Follow Route 77 past the visitor center and past the lake to the parking area for Cunningham Falls. It's about 11/2 hours from the District. If you want a place to change, there are bathhouses available at the lake, but you'll have to pay a parking fee of $3 for Maryland cars, $4 for out-of-state cars. If you want to learn about waterfalls on a fun, day-long field trip, sign up for the Aububon Naturalist Society's foray, "Waterfalls on a Summer Day." It's scheduled for August 20, all day long, and costs $16 ($11 for ANS members). Call 652-5964.