Some Denver streets have bicycle lanes, leaving a patchwork of disjointed routes throughout the city. There are over 850 miles of paved, off-road, bike paths in Denver parks and along bodies of water, like Cherry Creek and the South Platte. This allows for a significant portion of Denver's population to be bicycle commuters and has led to Denver being known as a bicycle-friendly city. Some residents are very opposed to bike lanes, which have caused some plans to be watered down or nixed. The review process for one bike line on Broadway will last over a year before city council members will make a decision. In addition to the many bike paths, Denver launched B-Cycle – a citywide bicycle sharing program – in late April 2010. The B-Cycle network was the largest in the United States at the time of its launch, boasting 400 bicycles.
Denver is in the center of the Front Range Urban Corridor, between the Rocky Mountains to the west and the High Plains to the east. Denver's topography consists of plains in the city center with hilly areas to the north, west and south. According to the United States Census Bureau the city has a total area of 155 square miles (401 km2), of which 153 square miles (396 km2) is land and 1.6 square miles (4.1 km2) (1.1%) is water. The City and County of Denver is surrounded by only three other counties: Adams County to the north and east, Arapahoe County to the south and east, and Jefferson County to the west.