A retreat can either be a time of solitude or a community experience. Some retreats are held in silence, and on others there may be a great deal of conversation, depending on the understanding and accepted practices of the host facility and/or the participant(s). Retreats are often conducted at rural or remote locations, either privately, or at a retreat centre such as a monastery. Some retreats for advanced practitioners may be undertaken in darkness, a form of retreat that is common as an advanced Dzogchen practice in the Nyingma school of Tibetan Buddhism.
Spiritual retreats allow time for reflection, prayer, or meditation. They are considered essential in Buddhism, having been a common practice since the Vassa, or rainy season retreat, was established by the founder of Buddhism, Gotama Buddha. Retreats are also popular in many Christian churches, where they are seen as mirroring Christ's forty days in the desert, including evangelical Protestantism, Roman Catholicism and Anglicanism.