Religious tourism is that form that is exclusively or strongly motivated for religious reasons. One of the oldest types of tourism and a worldwide phenomenon of religious history, it can be differentiated into various forms. The short-term religious tourism is distinguished by excursions to nearby pilgrimage centers or religious conferences. The long-term describes visits of several days or weeks to national and international pilgrimage sites or conferences. Organizational forms of religious tourism can be distinguished by definitive characteristics such as number of participants, choice of transport, seasonal travel, and social structure.