The Capital Crescent Trail is an 11-mile arc of wooded refuge that runs through the heart of suburbia and deep into the city, from Silver Spring in the northeast to Georgetown in the southwest. (Michael S. Williamson/The Washington Post)

It’s easy to take your most reliable running buddy for granted, or to forget, over time, how lucky you are to have that one friend who’s truly there anytime you want to go for a bike ride.

I’m referring, of course, to myself and the Capital Crescent Trail, an 11-mile arc of wooded refuge that runs through the heart of suburbia and deep into the city, from Silver Spring in the northeast to Georgetown in the southwest. If it’s weird for an adult to express affection for a sloping stretch of pavement, to admit a crush on crushed gravel, so be it. I’m certainly not the only one.

“When you try to estimate . . . what a trail like this is worth,” says Jake Lynch, spokesman for the Rails-to-Trails Conservancy, a national advocacy group, “that sort of value is priceless. You can’t put a price on it.”

“You’re seeing the Potomac. You’re seeing the woods. You’re getting out of the urban environment almost immediately,” says Ron Tripp, chairman of the Coalition for the Capital Crescent Trail, the local volunteer organization that helped get the trail built, beginning in the late 1980s, and now maintains and improves it.

“It provides this rural wooded setting. . . . It is a very convenient place to get out of an urban environment and do whatever [you] want to do.”

Indeed it is. I’ve walked, run and biked every inch of the CCT hundreds of times over the years — in the dark and at dawn, in 95-degree summers and 10-degree winters, alone and with groups of more than 100. I know the location of every water fountain, pothole, access point and secluded emergency pit stop. I plan my workouts around them. We all do.

Yet the trail is also a major commuter artery, a rush-hour bike highway whose traffic increases every year. That dual purpose makes the CCT a rare and valuable asset among the nation’s 1,768 rail trails, which cover more than 20,000 miles.

A 2006 survey, the most recent, revealed that more than 1 million people used the CCT annually, a total that Lynch and Tripp are certain has been greatly surpassed in the ensuing seven years. But even that outdated figure puts the CCT among the most heavily traveled rail trails in the United States, along with the Minuteman Bikeway outside Boston and the Midtown Greenway in Minneapolis. At almost every point where coalition volunteers counted trail users, cyclists were dominant, with runners second.

“When we’re talking about a trail like the CCT,” says Lynch, “the two things are urban utility . . . and public health, making sure there are pathways for people to walk and stroll.”

The conversion of unprofitable, abandoned railroad rights-of-way to trails began in 1983 with the passage of federal legislation allowing “railbanking,” which keeps sometimes lengthy corridors of land intact but diverts them to other uses.

The CCT was completed in pieces between 1988 and 2003, though the stretch from the tunnel under Route 355 in Bethesda to the Lyttonsville area of Silver Spring, known as the Georgetown Branch, remains unpaved and retains an “interim” designation.

“The timing on that conversion was ideal,” Tripp says. “There were just enough people looking forward at the time to see the value.”

The CCT has its problems, not the least of which is that the currently unfunded Purple Line light rail would run right down the Georgetown Branch. Even if a proposed 12-foot-wide paved trail is built alongside it, I’d have to reserve judgment about using it. That would be a very different experience from running on crushed gravel beneath overhanging limbs.

In October, the only violent attack anyone can remember on the CCT occurred when a woman was knocked unconscious and sexually assaulted while running on the trail one evening between Massachusetts Avenue and MacArthur Boulevard. The case remains unsolved. Some months earlier, there were two attempted robberies and a robbery farther north.

Despite those incidents and its heavy use, the CCT remains one of the safest, most graffiti-free stretches of public land you’ll find. On the three-plus miles they patrol between Bethesda and the District line, Maryland-National Capital Park Police responded to just 20 crime reports in 2012, only a handful of them for serious offenses, according to officer Sabrina Pirtle.

And of course, on weekends in good weather the trail is so crowded that some friction is inevitable as speedy cyclists tangle with slower walkers and runners. There have been collisions with cars where the trail crosses roads. Tussles continue about other future development.

“The biggest problem the trail has,” Tripp says, “is that it’s a victim of its own success.”

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