You never know what you might find behind a wall June 17, 2023 by Robert Huntington A man knocked down a wall in his basement. He found an abandoned underground city that was once home to 20,000 people. Derinkuyu, a subterranean city in Turkey that stretches 280 feet below Earth's surface, was rediscovered by a man looking for his lost chickens. www.businessinsider.com Views: 29