* BIGGER THAN LIFE: There aren't many things worth getting up early for on a Sunday morning, but the Tour de France is high on the list. Especially if you have the chance, as you will on July 17 starting at 7 a.m. at the Arlington Cinema 'N' Drafthouse, to watch on the big screen a potentially crucial stage studded with long climbs that ends way up in the scenic Pyrenees. Even better, if you go you'll help out two good causes, the Lance Armstrong Foundation, which continues its well-known efforts to fight cancer, and the Davis Phinney Foundation, which focuses on Parkinson's and is named for one of the United States' best-ever riders, who suffers from the disease.

That day's stage, the 15th of 21 in the event, starts in Lezat-sur-Leze and ends 205.5 kilometers later and 1,464 meters higher in Saint-Lary-Soulan (Pla-d'Adet). The riders briefly will detour into Spain and then will gear up for a soul-testing group of climbs that peaks out at 1,669 meters in a place familiar to Armstrong aficionados. He won the last stage to pass through Pla-d'Adet, in 2001, grabbed the leader's yellow jersey there and wore it to the finish.

"It's a good one to show on the big screen," said John Tegeris of Route 1 Velo, the longtime Washington area cycling club that is organizing the Stage 15 event, which will include a buffet breakfast, a raffle and a silent auction, with all profits going to the Armstrong and Phinney charities. Tegeris, an avid cyclist, will take off soon after the event to watch the last week of the Tour in person. "If you haven't seen one on the big screen, it really is an experience."

For more details and to buy tickets, visit www.route1velo.com. For more about Stage 15 and the rest of the Tour de France, check out www.letour.fr/. . . .

The Mid-Atlantic Off-Road Enthusiasts will head to Fountainhead Regional Park in Fairfax Station on Saturday for an intermediate-rated ride starting at 9:30 a.m. Visit www.more-mtb.org for more information. . . .

The EX2 Off-Road Triathlon, which includes a three-quarter-mile swim, a 14.2-mile mountain bike ride and a 5.1-mile trail run, will be held on July 17 at 10 a.m. at Rocky Gap State Park in Flintstone, Md. To register, visit www.ex2adventures.com.

* MAKE A SPLASH: The Potomac Whitewater Festival, which includes clinics, freestyle and squirt boating competitions, two parties and the dramatic Great Falls Race, will be held on Friday and Saturday on and along the river. All proceeds will go to American Whitewater, a nonprofit long engaged in protecting the nation's waterways. For directions, more details and to find out how to register for the event, visit www.potomacfest.com/

* SOUTH OF THE BORDER: The Blue Ridge Section of the American Alpine Club will meet tomorrow at 7:30 p.m. at the Rhodeside Grill at 1836 Wilson Blvd., Arlington. Simon Carr and Jeanette Helfrich will host a slide show on El Potrero Chico, a noted climbing site not far from Monterrey, Mexico. Nonmembers are welcome. For more information, visit http://brs.alpineclub.org/.

-- John Mullen

mullenj@washpost.com