America is known for its enduring love affair with the automobile. But in the last few years cities across the US have reported a surge in bicycle use, as people search for greener, healthier - and cheaper - transport options. The BBC's Daniel Nasaw looks at what Washington DC is doing to push two-wheeled travel.
America is a land of long distances, of thousands of virtually empty square miles of prairie, farmland and baking desert and frozen tundra.
US cities sprawl on a level unseen in Europe, Canada, and Australia, a consequence of transport priorities that have long favoured motor vehicles. And in all but a handful of US cities, it is virtually impossible to get by without a car.
But in recent years, amid widespread concern about US dependence on foreign oil, high petrol prices, signs of global warming and an obesity epidemic, a number of US cities have taken steps to increase bicycle usage.
These cities hope that by adding relatively low-cost bicycle lanes, bike parking and bike sharing programmes and making other city plan adjustments, they can lessen traffic congestion, reduce the strain on public transport, and promote healthier citizens.
Jim Sebastian, head of Washington DC's bicycle and pedestrian programme, says his goal is to make the nation's capital "one of the most bike friendly cities in the country".
"This is something that's clean, healthy, efficient," he said. "People are demanding it. It's going to bring people to the city and keep people in the city."
In recent years, the US capital has painted bicycle lanes onto busy thoroughfares, shielded bike tracks from traffic behind lines of parked cars, and altered traffic lights to accommodate cyclists.
A new bike sharing programme lets members borrow a cycle from a station near, say, the office, and it ride home - or to the pub - where it can be returned to another sharing station.
The effort has got Washington commuters pedalling, with roughly 2.3% of residents biking to work in 2008, up from 1.16% in 2000, according to the US census. That number has likely grown in the last two years. Nationwide, the figure is about 0.6%.
"The newer bike facilities have made more people excited about biking and feel better about biking," said Lori Leibowitz, a 29-year-old HIV/Aids policy analyst who commutes several miles every day on her bicycle.
"It's more fun than the Metro, it's more fun than walking, it's way more fun than driving. It's like taking what used to be the least fun part of the day and making it among the most fun part of the day."
As cycling has increased, statistics show little discernable increase in deaths in cycling road accidents. According to the National Highway Transportation Safety Board, three cyclists were killed in DC traffic accidents in 2005 - and none in 2009.
Nationally, cities that have invested in bicycle infrastructure have seen a marked increase in cycling as compared to those content to rely on automotive traffic. According to the League of American Bicyclists, the most bicycle friendly cities saw a 69% increase in bike commuting between 2000 and 2008, compared to 48% for the top 70 US cities on average.
While cycle-commuting proponents laud the progress, they note even the most bike-friendly US cities have years to go before catching European cities such as Copenhagen, where an estimated 30% of residents commute to work or school on a bicycle.
But Copenhagen cyclists have benefited from decades of pro-bike planning decisions, while US urban planners must overcome a century of energy politics and urban policy designed to promote vehicle use.
"There was an enormous American economic engine built around the continuing expanded use of the automobile," said Prof Owen Gutfreund of the urban affairs faculty at Hunter College in New York, and author of Twentieth-Century Sprawl: Highways and the Reshaping of the American Landscape.
Beginning in the 1920s, American urban growth was planned to encourage residents to leave congested city centres and move to the peripheries or to newly created suburbs. There, homes, schools, shopping and the office were all too far away to walk or cycle.
By the 1970s, many urban centres were nearly empty, their populations having evacuated to the suburbs. Detroit - the home of the US vehicle industry - has lost roughly half its population from its height in 1950, even as the surrounding region has grown.
But since the 1990s the US has enjoyed an urban renaissance, with cities such as Little Rock in the state of Arkansas and Louisville in Kentucky embarking on ambitious programmes to draw residents and businesses back downtown.
And in Washington, areas devastated by urban rioting in the late 1960s have seen a resurgence, including some of the areas most popular with cycle commuters.
"There's been a real renaissance in American cities in the past 10 to 15 years," said Kenneth Jackson, an urban historian at Columbia University. "On the other hand, we are still a suburban nation. Even though there's a move to walk and ride bikes... it's going to be tough to change the culture."
But in Washington, Mr Sebastian of the transportation department said cities should try.
"There are a number of barriers to bicycling," he said, "and it's the job of the city... to try to knock down those barriers."