The Toraja are an ethnic group indigenous to a mountainous region of South Sulawesi, Indonesia. Their population is approximately 650,000, of which 450,000 still live in the regency of Tana Toraja. Most of the population is Christian, and others are Muslim or have local animist beliefs known as aluk ("the way"). Torajans are renowned for their elaborate funeral rites, burial sites carved into rocky cliffs, massive peaked-roof traditional houses known as tongkonan, and colorful wood carvings. Toraja funeral rites are important social events, usually attended by hundreds of people and lasting for several days. Before the twentieth century, Torajans lived in autonomous villages, where they practised animism and were relatively untouched by the outside world. In the early 1900s, Dutch missionaries first worked to convert Torajan highlanders to Christianity. When the Tana Toraja regency was further opened to the outside world in the 1970s, it became an icon of tourism in Indonesia: it was exploited by tourism developers and studied by anthropologists. By the 1990s, when tourism peaked, Toraja society had evolved significantly, from its agricultural beginnings into a largely Christian society.