Covering an area of almost five thousand square kilometres, from the northern tip of Danau Toba to the border of Aceh, the Karo Highlands comprise an extremely fertile volcanic plateau at the heart of the Bukit Barisan mountains. The plateau is home to over two hundred farming villages and two main towns: the regional capital, Kabanjahe, and the popular market town and tourist resort of Berastagi .

According to local legend, the Karo people were the first of the Batak groups to settle in the highlands of North Sumatra, and, as with all Batak groups, the strongly patrilineal Karo have their own language, customs and rituals, most of which have survived, at least in a modified form, to this day. These include convoluted wedding and funeral ceremonies, both of which can go on for days, and the reburial ceremony , held every few years, where deceased relatives are exhumed and their bones are washed with a mixture of water and orange juice.

When the Dutch arrived at the beginning of this century they assumed, mistakenly, that the Karo were cannibals. The now-defunct Karonese tradition of filing teeth, combined with a fondness for chewing betel nut that stained their mouths a deep red, gave the Karo a truly fearsome and bloodthirsty appearance. In fact, the Karo, alone amongst the Batak tribes, abhorred cannibalism, though their traditional animist religion was as rich and complex as any of the other Batak faiths. Today, over seventy percent of the Karo are Christian, fifteen percent Muslim and the rest adhere to the traditional Karo religion. Every member of Karonese society is bound by obligations to their clan, of which there are five, and seen as more important than any religious duties.