A bicyclist rides on a sheltered bike lane on 9th Avenue at 21st Street in New York City in May 2008. (Helayne Seidman for The Washington Post)

No one who bicycles would immediately pick New York City over, say Boulder, Colo., as a two-wheeled heaven — at least not without extensive preparations to defend that argument.

But that's exactly what Bicycling Magazine did Wednesday, reasoning in its October issue that the vast improvements for cyclists in the nation's largest city trump the wide bike lanes of San Diego or the views from high in the Rockies.

"Traditionally, it is always one of the presumed cycling paradises, like Portland, Oregon," Bill Strickland, the magazine's editor in chief, said of the biennial survey. "This year, the more we thought about it ... [we realized] that bikes are kind of an indicator of the vibrancy of the economy and the safety of the streets," as well as a city's overall livability.

"We just thought," he added, "that New York is at the leading edge of how urban areas are going to start making urban life better"  — in part, through cycling.

The program, spearheaded by former mayor Michael Bloomberg, has resulted in 350 miles of new bike lanes in recent years, many of them separated from traffic by concrete barriers. The city's bike share program has 96,000 subscribers, making it, not surprisingly, the nation's largest. "This bike share thing just seems to be such an influential part of getting more people on bikes. And New York has just done such a phenomenal job," Strickland said.

Strickland noted that the magazine's decision takes in the impact bikes are having on all five of New York's boroughs, not just Manhattan. Bicycling in New York is a portrait of diversity, from road racers to commuters to food delivery people, with venues as different as the bike path over the Brooklyn Bridge to a velodrome in Queens. The city hosts the oldest group ride in the U.S., the Gimbel's ride.

Rounding out Bicycling's top five: another urban bicycling center, Chicago, which won praise for a new plan to build 100 miles of new buffered and barricaded bike lanes; Minneapolis, which has one of the biggest bike share programs in the country, per resident; Portland, where a proposed apartment project will have 1,200 parking spaces for bikes; and Washington, D.C., with a regional trail system that encompasses almost 70 miles in total.

So where is the worst place to ride? Well, it's right near New York — Suffolk County, Long Island. Again, the magazine's thinking was counter-intuitive, Strickland said: While people may think of flat, wide-open suburbs as conducive to cycling, the roads are really not built for cyclists.

"Really, right now, the worst city is in the suburbs," Strickland said. "We picked Suffolk to be emblematic of that."

"Suburban streets were made to move people out of their homes to stores, or out to work," not for bicycles, he said.

The magazine found that Suffolk County is always one of the most dangerous places in the United States to ride a bicycle. In 2008, the county was the site of 23.8 percent of  all fatalities to cyclists in New York state, despite having less than 8 percent of the state's population.

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