There is a small colony of naked men who spend their days frolicking in streams and hiking woodsy trails not six miles from the Washington city limits.

These men apparently have had some prior contact with civilization. One was sufficiently acquainted with the English language to frame the simple greeting "Good luck," when he was passed by two startled fishermen last week.

The naked man apperared well-fed and healthy. He was not entirely bare;he had strapped on crude leather sandals that bore a striking resemblance to up-to-date fashions from George town Leather Design.

He was portly, middle-aged and his round face was framed in a reddish beard. He smiled at the intruders.

The naked man emerged from the bushes about a half-mile down Difficult Run from the Rte, 193 bridge below Great Falls. Another quarter-mile downstream toward the Potomac, two other nude men were observed splashing and playing, child-like, in a deep pool in the Run.

These naked men were younger and offered no greeting; they grew hostile and surly when the fishermen stopped to watch them at play.

The colony of unclothed humans is but one of the unexpected features of a fishing trip at Difficult Run. One angler recalls fishing the Potomac there when Park rangers moved in, en masse.

"Anyone here seen a big brown bear?" they asked.

It turned out one had been lost by a touring circus and had worked its way up the river.

Another fisherman reportedly saw a mountain lion on the rocky shore about 10 years ago. A rabid squirrel blocked a fishing party's way a couple of years back; it was chased away with rocks and sticks. Hawks, foxes, deer and raccoons also have been sighted.

These untamed creatures thrive a matter of minutes from the CIA and Arby's because Difficult Run is, as its name implies, a tough place to get to.

The walk to the Potomac from Rte. 193 is a good 30 minutes. The first is moderate over a path cut through the brush. The second half is arduous climbing over steep rocks. Copperheads are common; travel after dark can be dangerous.

At the end of this haul is just another chunk of the Potomac, from all appearance. But for the fisherman, it has its pluses.

Resting as it does just below Great Falls, the Difficult Run area has a good supply of fast water passing by deep pools. Fish congregate at spots like that and there is good to excellent smallmouth-bass fishing during the summer.

The smallmouth bite well on minnows or can be lured in with Rapalas. Fish the edges of the fast water with the minnow two or three feet below a bobber.

After dark, when bobbers can't be seen, anyway, the scene shifts to catfish. There are reports of big cats, 10 pounds and over, coming out of the deep water just where Difficult Run spills into the river.

The cats bite just about anything, but minnows worked well last week, landing a fine four-pounder on light tackle, and the favorite local bait seems to be raw chicken livers.

Just glob the chicken liver on a medium-sized hook and heave the whole mess, weighted down with an ounce or so of lead, into the deep water.

Once it sinks, don't move it or it will get caught in the rocks and you lose your rig. Just let it sit and eventually a cat will come along and slurp it up.

We were well into our latenight catfish angling Wednesday when a skinny raccoon showed up. Thesebeasts are supposed to be extremely wary, but this one was hungry and apparently attracted by our chicken livers.

"Shoo," we shouted, and the coon trotted three steps closer.

"Vamoose," we screamed and the coon moved closer.

We shined flashlights in its eyes and hurled sticks and little stones his way. The raccoon kept moving in like a big, dumb, friendly dog.

Finally and inevitably, with the coon just 10 yards off, we got simultaneous hits on our catfish lines. Stumbling and flailing like wounded centipedes, we tried to keep lights on the coon, hurl sticks and stones to keep it back, crank in the cats and protect our stringer and our chicken livers all at once.

Needless to say, we lost the fish. The naked men could have handled it.