There is an close and interesting relationship between tourist travel and religious pilgrimage. Structurally (infrastructure, organization, and geography), they are almost identical. For example, like tourist attractions, almost anything can be a sacred site with the right story/message/signing. Many argue that pilgrimage and tourism are almost identical from a psychological perspective (motivations and experiences), as well. And, finally, tourists often partake in pilgrimage, and pilgrims in tourism, on the same trips.
From the website:
"Welcome to Sacred Destinations — a catalogue and travel guide to more than 1,500 (and counting!) sacred sites, holy places, pilgrimage destinations, historical sites, religious buildings and religious artifacts around the world."