At long last, Google Maps has routes specifically for bikes.

With the click of a mouse, the new feature allows you to plot the best (and flattest!) ride from Point A to Point B. Several cities, including New York, Minneapolis, San Francisco and Portland, Oregon, have bike-specific mapping sites. But Google is rolling it out in 150 cities nationwide and announcing it Wednesday at the 10th Annual Bike Summit in Washington, D.C.

"This has been a top-requested feature from Google Maps users for the last couple years," says Shannon Guymon, product manager for Google Maps. "There are over 50,000 signatures on a petition."

The news thrilled bike advocates, who have for years been pushing – and petitioning – the search giant to include bike routes on Google Maps. No longer do they have to rely upon paper maps or open-source DIY map hacking or crazy-cool helmet-mounted heads up iPhones.

"This new tool will open people's eyes to the possibility and practicality of hopping on a bike and riding," says Andy Clarke, president of the League of American Bicyclists. "We know people want to ride more, we know it's good for people and communities when they do ride more – this makes it possible. It is a game-changer, especially for those short trips that are the most polluting."

Cyclists will have to map their victory lap from their desks, because Google's cool mapping tool is available only on a computer for now.

"Making the bike-route tool available on Google Maps for mobile devices is a high priority,” Guymon says. But it’s a priority without a launch date.

To create the mapping tool, Google developed an algorithm that uses several inputs – including designated bike lanes or trails, topography and traffic signals – to determine the best route for riding. The map sends you around, not over, hills. But if you really want to tackle that Category 1 climb, you can click and drag the suggested route anywhere you like, just like you can with pedestrian or driving routes. Users can suggest changes or make corrections to routes using the ever-present "report a problem" feature on Google Maps.

Google kicked its bike-mapping effort into high gear in October when it started using improved datasets that provided more specific information about trails, street details and more granularity on college campuses. The Rails-to-Trails Conservancy provided Google with information on 12,000 miles of bike trails nationwide, and the League of American Bicyclists helped gather data on bike lanes and so forth.

“We’ve got a five-person team in Seattle that has spent the majority of its time working on this project since October,” says Guymon.

To test the tool, bike-commuting Google employees vetted suggested routes against their own experience, pointing out discrepancies on routes or time allowances.

Google Maps for bikes has a unique look and feel. Bike trails are prime cycling turf – "They're like the highways for cyclists," Guymon says – so they're indicated in dark green. Streets with dedicated bike lanes are light green. And streets that don't have a bike lane but are still a decent route because of their topography, light traffic or other factors are indicated by dotted green lines.

Don't go looking for turn-by-turn GPS-based navigation though. That feature remains strictly auto-centric.

Freelance reporter Mary Catherine O'Connor lives in San Francisco, with her dog, husband and three bikes.

*Photo: Bikeportland.org/Flickr *