Think metric.

September is the under-the-radar National Century Month for bicyclists. Not only are cyclists encouraged to pedal a century—100 miles— in a day, but they can also choose from the 25-mile quarter century, 50-mile half century and the 63ish-mile metric century.

That metric century is a beautiful thing.

It’s not 100, but it is

Less daunting than 100 miles, 100 kilometers is a wonderfully accessible achievement for an improving recreational rider and a nice few hours in the saddle for experts. Many seasoned European bike tourists carrying tent and panniers have 100 kilometers as their daily goal before setting up camp for the night.

"A metric century certainly is an attainable goal and it doesn't have to take all season," says Littleton Bike and Fitness owner Dave Harkless. "People can get to it reasonably quickly. A metric century is a nice bench."

According to longtime bicycling advocate Dave Topham, co-chairman of the Granite State Wheelmen's  Tri-State Seacoast Century September 26 and 27 in Hampton, the metric century was included as a bicycling standard many years ago by the League of American Wheelmen. Now called the League of American Bicyclists, the cycling organization promoted riding by encouraging riders to complete the aforementioned centuries and collect patches.

One hundred is a nice round number, whether it be miles or kilometers.

"The metric century is a real accomplishment for many recreational riders," says Topham. "If they are in decent shape, cyclists can ride 50, 60 or 70 miles. If they are trying to do a (100-mile) century, sometimes those last 20 miles can burn them out."

The GSW ride has a metric century.

Where else to ride?

There are a a few others coming up too. In Massachusetts, the Charles River Wheelmen's September 20 Soughegan River Tour contains one as does the October 4 Major Taylor Century through the Blackstone Valley put on by the Seven Hills Wheelmen. There's even an ominous sounding one for mountain bikers called Mike's Maine Metric Mountain Mash scheduled for October 12 in Camden, Maine.

"You certainly see more century rides than metric rides," Harkless said.

There are many places—with small stores along the way to rest and refuel—where riders can create their own metric century.

That's where the web site mapmyride.com comes in.

"That is a great place to go," says Harkless. "Build it, save it, print it and go. The elevation profile is the best tool there."

Both sides of the Connecticut River in New Hampshire and Vermont lend themselves to long distances with rolling hills, farms, fields and vistas. The Mount Washington Valley in tandem with western Maine has hills that are more sedate than the rugged notches  and gentle farmland too. New Hampshire's 18 miles of seacoast are part of flattish terrain that ventures into neighboring states.

Got tips?

Granite State Wheelmen president Bill Kennedy, also an LAB certified instructor, says both hardcore riders and riders new to cycling are drawn to the metric century.

"Some hardcore riders might not have the time to do more, so they get up early and ride the metric century," says Kennedy. "There are also riders who may have gotten a bicycle in the spring and want something beyond their weekly 20-mile ride. They look at it as a challenge. We also see families with teenagers. The bulk of the people want something more than that evening club ride but aren't ready for the whole 100-mile century."

Cyclists must ride in order to prepare, but Kennedy also suggests to look at a metric century as a few parts. Ride the first third, rest. Take the second third, rest again. Do it a third time. Or think of it as two 25 mile rides, with a final 16 mile leg.

"Many people think, 'My gosh, 60 miles. I'm so tired.' But stop, rest, get off your bike and stretch."

He also suggest adhering to that adage drink before you're thirsty, eat before you are hungry and rest before you are tired.

Whether it be an electrolyte drink and energy bar or banana, fig  newton and water, stay hydrated and well fueled.

"I suspect if you ask 100 people why they do a metric century you will get 100 different answers," says Kennedy. "But I bet most will have' because it's fun' in there somewhere."