In architecture, the position of a building on its site. In Mesopotamia and Egypt, as well as in pre-Columbian Central America, a building's important features, such as entrances and passages, faced the rising sun. Mosques are oriented so that the mihrab faces Mecca. Christian churches have usually been oriented with the apse or altar at the eastern end. Orientation is frequently planned to take maximum advantage of daily and seasonal variations of sunlight. A structure's optimal orientation is usually a compromise between its function, location, and the prevailing environmental factors of solar radiation, light, humidity, and wind that make up the site's microclimate.