The biggest mass gatherings involve the divine

Procession of the carriage of the Black Nazarene in Manila, Philippines. Ezra Acayan/Getty Images

An opportunity to worship at a sacred site is one of the biggest motivators for people to travel halfway across the globe and endure hours of physical discomfort navigating chaotic crowds. Religious pilgrimages are among the oldest forms of travel, and cheap airfare has made them some of the planet’s largest mass-migration events. Every religious movement has its own holy hubs that bring together believers from all corners of the world. Muslims journey to Mecca, Saudi Arabia, for the Hajj, arguably the most widely known annual religious pilgrimage and a mandatory lifetime rite for every adult Muslim. The central gathering spot is Mecca’s mosque, where pilgrims collectively circle a stone shrine called the Kaaba, believed to have been built by the main prophet in all Abrahamic religions, Ibrahim, aka Abraham. Saudi Arabia reaps a windfall as the custodian of Islam’s holiest sites: Last year, the Hajj drew over 1.6 million pilgrims, who paid from $5,000 to over $25,000 for tours that include government permit costs, accommodations, transportation, and food. Some countries, including Nigeria and Indonesia, subsidize part of the cost of the trip for their citizens. Hasidic Jews trek to Ukraine…where Uman, a small city about 150 miles south of Kyiv, hosts a religious celebration every September for Rosh Hashanah (Jewish New Year). Up to 60,000 believers—from Israel, the US, and Europe—pay their respects at the 18th-century tomb of the revered Rabbi Nachman of Breslov, who started the Breslov Hasidic movement. The pilgrimage continued to take place even after Russia invaded Ukraine in 2022. Hindus gather to bathe in the rivers…for the Maha Kumbh Mela festival, held once every four years. Known as the world’s largest human gathering, last year’s festival drew over 660 million people. Sites rotate among four cities located on the banks of the sacred Ganges, Godavari, and Shipra Rivers, where pilgrims partake in purifying bathing rituals and spiritual study. Catholics flock to Manila, Philippines…for the annual Feast of the Black Nazarene, which revolves around a 30-hour procession with a replica of a sacred 17th-century wooden statue of Jesus, blackened by fire. Almost 10 million devotees walked barefoot alongside the carriage carrying the effigy through city streets last year. Aside from its spiritual value…religious tourism is a massive industry, generating nearly $290 billion in economic activity as of 2024, per Grand View Research.