A public park is a place where people can go to spend time away from the home in an outdoor environment. Parks have many features designed to give the most options possible to park visitors. How a park shapes up depends greatly on the natural environment it is located in. It may consist of grassy areas, rocks, soil, and trees, but may also contain buildings and other artifacts such as monuments, fountains, or playground structures. Many parks have fields for playing sports such as football and baseball. They may also have paved areas for games such as basketball. Many parks have trails for walking, biking, and other activities. Often, the smallest parks are in urban areas, where a park may take up only a city block or less. Urban parks often have benches for sitting, and may contain picnic tables and barbecue grills.
Additionally, many parks engage the community by providing venues for recreation and events. Many parks hold outdoor concerts where visitors can enjoy live entertainment. Parks are traditionally selected to host traveling carnival shows. These carnivals have mechanical rides that people can enjoy for a small fee. Carnivals also have game booths, video games, and food available. Parks are sometimes divided into active and passive recreation areas. Active recreation involves cooperative or team activity, including playgrounds, ball fields, swimming pools, gymnasiums, and skate parks. Active recreation such as team sports, due to the need to provide substantial space to congregate, typically involves intensive management, maintenance, and high costs. Passive recreation, also called "low intensity recreation", emphasizes the open-space aspect of a park and allows for the preservation of natural habitat. It usually involves a low level of development, such as rustic picnic areas, benches and trails.