The genre arose during an era when the remnants of lost civilizations around the world were being discovered by Westerners, such as the tombs of Egypt's Valley of the Kings, the semi-mythical stronghold of Troy, the jungle-shrouded pyramids of the Maya, and the cities and palaces of the empire of Assyria. Thus, real stories of archaeological finds by imperial adventurers succeeded in capturing the public's imagination. Between 1871 and the First World War, the number of published lost world narratives, set in every continent, increased significantly.