From the 1840s onwards, long-distance trade caravans began pushing deep into the interior of what would become Kenya. Led by Swahili and Arab traders, the caravans sought one thing above all others: ivory. Elephant tusks were worth a fortune in India and Europe, where they became piano keys, billiard balls and decorative objects. Kenyans who lived near elephant herds were recruited as porters, hunters and guides. Many never came home. The caravans that crossed the land laid the first paths that would later become roads, railways and colonial routes.