text: The day without cars is part of an improvement campaign that began in bogota in the mid-1990s. It has seen the consruction of 118 miles american city, according to mockus, the city's mayor. Parks and sports centers also have bloomed throughout the city; uneven, pitted sidewalks have been replaced by broad, smooth sidewalks; rush-hour restrictions have dramaticly cut traffic; and new resturants and upscale shopping districts have cropped up.