Lidar analysis, Tikal (IMAGE) Brown University Caption A recent lidar analysis revealed that an area once assumed to be natural hills, center, near Tikal's Lost World complex, right, is actually an 1,800-year-old ruined citadel. Credit Thomas Garrison/PACUNAM Usage Restrictions Photo credit required License Original content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.