text: Cold nights and warm days caused the warmer layer of air to trap car emissions and desil fuel was blamed. we the people want to stop the pollution and eliminate it once and for all so the People proposed " A day without cars". It's part of an improvement campaign that began in Bogota in the mid-1990s. This campaign has seen the construction of 188 miles of nicycle paths, the most of any Latin American city, according to the citys mayor. Parks and sports centers have beeen packed throughout the city, Sidewalks have been redone, rush-hour restrictions have cut traffic, new and more resturaunts have been built, and upscale shopping districts have cropped up.