The Lost City of Z, a fabled metropolis of unimagined riches deep in the Amazon rain forest, has eluded explorers for centuries. But recently documented traces of a well-planned constellation of walled settlements arranged around central plazas and linked together with arrow-straight roads in the Upper Xingu region of the Brazilian Amazon may be the civilization that gave birth to the legend, scientists say. Check out this and six more tales from cities lost and found.