Everyone heads to the mountains this time of year to see fall foliage, which makes for nasty traffic jams. Give me the valleys, anytime.

Along the Potomac this week, the dogwoods were fire red and the tulip poplars and sycamores were turning bright yellow. Clumps of blue flowers, presumably wild asters, blossomed along the banks and the water was gin clear and cool, already down in the 50s.

In Luray, Va., Nancy Sottosanti was scraping frost off her windshield every morning and enjoying the bright red of Virginia creepers twining up the trees. "It's freezing," she complained. But fishing on the South Fork of the Shenandoah behind her shop remained good. "One bunch of canoeists took three days to go eight miles on the river," she said. "They found a {fishing} hole and fell in love with it."

Near Harpers Ferry, W. Va., Nora Kelly said she was looking at the best time of the year on the river -- "cool, no bugs, and clear water at the perfect level for paddling."

"It's starting to look real pretty," Gene Clore said of the Rappahannock, which runs through his back yard in Fredericksburg, Va., "especially the last few days."

All these people run or work at boat liveries and these are curious times for them. Every year, just when the river turns so pretty you want to get it stuffed and save it forever, business drops off to near nothing.

Nonetheless, they are staying open for a few more weeks, some longer, in hopes of luring in the last few river runners with a taste for crisp autumn and its delights.

I set aside a day this week to fish the Potomac just above Great Falls, and while it was no highly successful fishing trip, it could not have been more invigorating.

Erik Rosenfeld took off from his job at Safeway and his roommate, Brad Miller, gave up an afternoon as an electrician to squire me around their home waters near Riverbend Park, a half-mile above the falls on the Virginia side, 15 minutes from the Beltway.

Rosenfeld said October is high season for large smallmouth bass, but a cloud of concern crossed his brow when he dipped a hand in the water. "Cold," he said, and so was the breeze, honking downstream on the heels of a northwester; not exactly ideal fishing conditions.

In my rented rowboat, I couldn't have cared less. Upstream, you could hear the burble of the first mild rapids. A pair of mallards flushed just ahead as we drew near; two Canada geese paddled away, harronking noisily; the sky was robin's egg blue, the air as clear as diamonds and there wasn't a sign of man in sight, all of which combined to make you feel uncompromisingly alive.

Unfortunately, it also added up to some lethargic bass and bluegills.

All the river fishing experts say October is a good time for big bass, but for best results once the water cools, you need live bait or artificial lures you can work slowly near the bottom of deep pools where the bass lurk.

This demands more patience and time than we had, so we went about our normal techniques, casting spinners and diving lures across the moving water until a few fat bluegills and a couple of decent-sized bass had hooked up. That took hours, but who was counting?

Autumn boating on rivers is not without some mild perils. When water temperature dips into the 50s it's a bad idea to capsize, and if the air temperature gets into the low 50s, you don't want to get wet and stay wet, so it's good to bring a change of clothes in a waterproof bag.

But there are plenty of gentle river stretches around the area that are safe for novices, like the Potomac at Riverbend or from White's Ferry to Seneca Breaks; the Shenandoah at Luray, the Rappahannock just above Fredericksburg, or any stretch of the flat-calm C&O Canal above Washington.

Of course, you'll need a boat and a little advice. The following outfitters will be open for at least the next couple of weeks, some longer, depending on the weather: Fletcher's Boathouse, Canal Road in the District, or Swain's Lock, Swain's Lock Road, Rockville, rent canoes to use on the C&O Canal and rowboats to take on the Potomac. Riverbend Park above Great Falls, Va., rents rowboats on the river until Dec. 1. River & Trail Outfitters, Knoxville, Md., offers guided fall raft trips and rental canoes on the Potomac and Shenandoah near Harpers Ferry. Shenandoah River Outfitters in Luray, Va., and Downriver Canoe Co. in Bentonville, Va., rent canoes on the upper Shenandoah, two hours' drive from Washington. Clore Brothers in Fredericksburg, Va., has canoes for novices on the gentle stretch of the river just above Fredericksburg and for skilled paddlers on more demanding stretches further upstream.

Those intimidated by cold water boating might consider hikes along many of the same waterways. But remember: Skip the crowded high country. Think valleys!