Talk about a Grand Design!

In 1963, a man in Turkey was renovating his home and in the process discovered a whole city - 25 metres underground! It is believed to have housed as many as 20,000 people and a well, school and various meeting spaces were also discovered. They also had production facilities for wine and olive oil. Some historians believe this city was created by a Bronze Age empire known as the Hittites, and was used right up until the end of the empire… in 1909! Here’s just a bit of background on the amazing Derinkuyu.
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https://www.youtube.com/watch?v=sADcF9GVdg0