Depictions of snakes are frequent among the many animal tunjos the Muisca people made as offerings. They are often shown with whiskered heads, as on these examples. Lakes were believed to be inhabited by mythical ancestors in the form of snakes that required offerings. One well-known ritual during which tunjos were offered to Lake Guatavita, north of Santa Fé de Bogotá, gave rise to the famous legend of "El Dorado" (The Gilded Man). Sixteenth-century Spaniards recount that, before taking office, each Muisca ruler was covered from head to toe in gold dust and conveyed on a raft to the middle of the lake. There, he threw quantities of gold objects into the water as offerings to the gods. In the centuries since the conquest in the 1530s, countless lives and great fortunes have been lost in attempts to recover the treasures from Lake Guatavita. One, undertaken at the end of the sixteenth century, cut a great notch into the mountain on one side of the lake in an effort to drain it. Many gold objects and other offerings, including an emerald the size of a hen's egg, were recovered from the edges of the lake bed. Many such efforts have followed, but the central zone of the lake remains untouched. In 1965, the Colombian government declared the lake a cultural heritage site and placed it under legal protection.