Illustration (after Alexander von Humboldt's sketch) of the interior and floor plan of an Inca house in Ingapirca. Ingapirca is a town in Ca簽ar Province, Ecuador, and the name of an Incan archeological site just outside the town. These are the largest known Inca ruins in Ecuador. This image was drawn by Johann Friedrich Gmelin (1748-1804), a German naturalist, after a sketch of Humboldt's. Humboldt (1769-1859) was a Prussian geographer, naturalist and explorer. The Inca Empire lasted from the 13th century until 1532 and its historic capital was Cuzco (in modern Peru).