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The itineraries listed on the website of BikeSherpa (www.bikesherpa.com), a newly launched bike tour company run by an American expat in Germany, are enough to make any adventure traveler grab their passport and hop on a bike, whether they're a newbie or have logged hours in the saddle.

There are comfortable rides through Germany's Black Forest, showcasing the country's gourmet cuisine and wineries; there's a challenging trek through Italy, Austria, and Slovenia for intermediate-level riders; and there's plenty in between, including a river cruise and cycling trip from Amsterdam to Bruges.

Just as enticing as the trips themselves: The fact that you can go for free.

Sign up as a host (which really just means you pick a trip and post it on the website) and get six additional people to join you trip, and your cost is cut by 50 percent. Sign up 12, and BikeSherpa picks up your whole tab. (ShermanTravel readers can also receive $100 off an eight-day supported trip featuring the food and wine of Tuscany, departing on September 10, which includes accommodations, most meals, and wine tastings, plus bike rental.)

It's all part of founder Robert Reimann's plan to use social media to build the company. BikeSherpa's motto is "Let's ride together," and its model is based on word-of-mouth (and mouse) referrals from friends and like-minded, bike-loving travelers.

To host a trip (and start working toward those killer discounts), you'll be responsible for selecting a trip itinerary (categories include Beer Connoisseurs, Gourmet Food Lovers, Road Bike Cyclists, and countries and regions) and communicating with potential fellow travelers. You post the trip on the website and start recruiting fellow riders (though you also have the ability of keeping a trip private, part of the beauty of BikeSherpa is connecting with other travelers based on your interests).

In other words, as the website emphasizes: "Tour hosts aren’t guides and don’t take on any tour service responsibility. Their role is to define the character of the group and help collect a fun bunch to travel with."

But if you'd rather just show up and ride, there are plenty of incentives for that, too. Some of BikeSherpa's trips boast unbelievably low prices: an eight-day guided cycling cruise from Amsterdam to Bruges (and vice-versa), with on-board accommodation on the river cruise ship MS Mystique and all meals included, for just $1,310. Or an eight-day intermediate-level independent trip from Passau, Germany, to Vienna, Austria, with meals and double-occupancy accommodation, for just $844.

A former Wall Street finance executive, Reimann says he's able to keep prices low because of his relationships with local operators throughout Europe. In addition, more experienced riders can cut costs further with an independent tour, for which they're on their own (but equipped with maps) to get from place to place. Luggage service is always included, however, as well as an emergency contact.

Reimann, who's always on hand via phone or e-mail to help travelers with questions, is also planning to add additional itineraries soon, including a trip through Transylvania, Romania, that includes a stop at Count Dracula's castle. "You're out in the countryside for part of the trip, staying in people's homes," he says. "It's just beautiful."

Bottom line: Don't be surprised if you see yours truly as the host for an upcoming trip.

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