Put your summer cycling to the test this month and next. Fall bike-ride season is here, so take a break from your usual club itinerary, celebrate Lance Armstrong's return to competitive cycling and venture out to see another part of your state or even country. The following are some of the most beautiful or challenging stretches of roads in the U.S.

You may have to battle some newbies at the start of your ride, but once you get out ahead, it doesn't matter. At the end of the day, after 100 miles, the perks of good food and drink combined with positive-karma points earned for raising money for a worthy cause make for a meaningful weekend.

ithinkiCanyons

, Sept. 20, $60 registration, $50 students, $200 relay team of four.

If you're a masochist, head to Salt Lake City for the second annual

ithinkiCanyons

ride, which features 12,000 feet of climbing over 110 miles. The cause is to end homelessness, with proceeds going to health-care provider the Fourth Street Clinic, and the rigor designed to symbolize the challenge the homeless encounter in their everyday battles. The ride reaches its highest point around mile 45, when cyclists climb Big Cottonwood, topping out at 8,526 feet.

Tour de Whidbey

, Sept. 27, $70 registration, $110 tandem team.

If peaceful, idyllic surroundings are more your cup of Powerade, venture out to Puget Sound in the state of Washington and ride 100 miles on Whidbey Island. Originating at a farm in the center of the island, the figure-eight

Tour de Whidbey

layout takes cyclists through rolling terrain that gains nearly 8,000 feet while providing gorgeous views of the sea. The Tour, which benefits the local Whidbey General Hospital, might be good for couples who want to stay a while. A ferry ride away from Seattle, the island is famous for its Penn Cove mussels, artists' collective, beautiful beaches and estate-grown wines.

Bike MS New York City

, Oct. 5, $50 registration.

The

New York City version

of the MS Bike Tour is unique in that, for a day, you can pedal on the highways of New York, unhindered by traffic. Manhattan is already famous for its bike trails leading from the south to the north of the island, but here, ride through tunnels that Robert Moses meant for cars and trucks, ascend Manhattan along the East River and under the Brooklyn Bridge, as the Empire State Building and Chrysler Building sit on your left. Century riders continue on to New Jersey on a steep descent through the Lincoln Tunnel before encountering challenging climbs in Palisades National Park. The return to Manhattan is marked by a ride across the majestic George Washington Bridge. While it can get a little congested at the beginning of the shorter 30-mile option, 60- and 100-milers get their own start, and things open up rather quickly.

Seismic Challenge

, Oct. 18-19, $75 registration, includes two nights accommodation.

Back-to-back centuries are made easier when you consider the landscape of the

Seismic Challenge

: the rugged coastline of Northern California. The event begins in Fort Bragg, travels down the San Andreas Fault into Sonoma County, through Redwood forests and into Marin County, where riders cross the ultimate home stretch as they traverse the Golden Gate Bridge. The event benefits the San Francisco AIDS Foundation, and while registration is inexpensive, there is a rather ambitious fundraising minimum: $2,200.

Tour du Rouge

, Oct. 18-23, $2,500 registration.

If you have more than a weekend to spare, and your legs and mind are willing, attempt the 538-mile

Tour du Rouge

from Houston to New Orleans, benefiting the American Red Cross. You'll also have to be willing to spend $2,500, with half of that going directly to the Red Cross. Riders get the chance to meet people living in the disaster site areas along the Gulf Coast. The route itself, which was meticulously mapped out by Houston native and former New Orleans resident Alan Bazard, is highlighted by an overnight stay in tents on Rutherford Beach in Louisiana. Other points of interest include a trek through a wetlands preserve, crossings of the Mississippi River and a 23-mile stretch on the New Orleans levees, which leads to the big finish in the French Quarter. Riders will average about 85 miles a day, but it is a very flat course, as the elevation gained is actually elevation lost, at 75 feet.

Fall Foliage Bike Festival

, Oct. 17-19, $30 registration.

If rolling hills and the colors of fall are your idea of an idyllic setting to push your Trek or Cervelo into gear, the

Fall Foliage Bike Festival

in Virginia's Shenandoah Valley might be the best place to get your century on. The festival is very much a family-oriented event, with rides starting at 10 miles and perks like free admission to attractions. Still, 100-milers take the first 48 by themselves before joining other loops, a stretch that takes one to the foot of the Allegheny Mountains, over rolling hills and across rivers and covered bridges. At the end of the day, enjoy what race organizer Barbara Wright calls "a taste of Southern hospitality," as the infamous Soup Lady cooks up vegetable, chicken and rice offerings to warm the soul.

Nate Herpich is a freelance writer and editor living in Brooklyn, N.Y. He has also written for the Wall Street Journal, the Christian Science Monitor and Sports Illustrated.com.