The following article contains an answer for the question: What is the name of the lake that once again swallowed the upper part of the amphitheater and the retaining wall after these were exposed for a time? , can you please find it? 

For years, stories circulated of a treasure being buried within the amphitheater. W. T. McWhorter was determined to find out if it was true, so he planned to dynamite the amphitheater on the day he was to transfer the deed to the CoE. Spectators attended the planned explosion, but it was stopped just in time by CoE attorney David Waid.The dam was completed, and Beaver Lake was at full height by June 1966. For all intents and purposes, Harvey's Monte Ne was gone. However, in times of drought, some of the structures become visible again. The lake dropped to its lowest level on January 22, 1977, more than 27 feet (8 m) below its average depth, and the amphitheater and bridges were visible for the first time in more than 10 years. Before the water flooded downtown Monte Ne again, the rest of the buildings were either bulldozed or moved to avoid problems for swimmers, boaters, and fishermen. The few bridges that spanned the lagoon and the amphitheater were not demolished.In 2006, the waters of Beaver Lake once again receded to their lowest level since 1984, just above 1,100 feet (335 m). This generated a new brief interest in Monte Ne and people were once again attracted to the edge of the lake to explore the remains. The upper part of the amphitheater and the retaining wall built for the never constructed pyramid were exposed for a time before being once again swallowed by the lake.The flooded Monte Ne has become a site of interest for scuba divers who dive by the amphitheater to get a look at the submerged structure. The water is moderately clear and temperatures comfortable.

Beaver Lake