Rediscovery
With the development of archaeology and the application of modern techniques, many previously lost cities have been rediscovered.
The Arabian city of Ubar (Iram of the Pillars) was abandoned after much of the desert city and its primary water source collapsed into a sinkhole. Once wealthy from trade, the region became lost to modern history and was thought to be only a figment of mythical tales. In the early 1980s a group of researchers interested in the history of Iram used NASA remote sensing satellites, ground penetrating radar, Landsat program data and images taken from the Space Shuttle Challenger as well as SPOT data to identify old camel train routes and points where they converged.
Machu Picchu is a pre-Columbian Inca site situated on a mountain ridge above the Urubamba Valley in Peru. Often referred to as the "Lost City of the Incas", it is perhaps the most familiar icon of the Inca World. Machu Picchu was built around 1450, at the height of the Inca Empire. It was abandoned just over 100 years later, in 1572, as a belated result of the Spanish Conquest. It is possible that most of its inhabitants died from smallpox introduced by travelers before the Spanish conquistadors arrived in the area. In 1911, Melchor Arteaga led the explorer Hiram Bingham to Machu Picchu, which had been largely forgotten by everybody except the small number of people living in the immediate valley.
Helike was an ancient Greek city that sank at night in the winter of 373 BC. The city was located in Achaea, Northern Peloponnesos, two kilometres (12 stadia) from the Corinthian Gulf. The city was thought to be legend until 2001, when it was rediscovered in the Helike Delta. In 1988, the Greek archaeologist Dora Katsonopoulou launched the Helike Project to locate the site of the lost city. In 1994 in collaboration with the University of Patras, a magnetometer survey was carried out in the midplain of the delta, which revealed the outlines of a buried building. In 1995 this target was excavated (now known as the Klonis site) and a large Roman building with standing walls was brought to light. The city was rediscovered in 2001 buried in an ancient lagoon.
Read more about this topic: Lost City