On Feb 14, 2017 the BBC released a video on their website entitled Turkey's secret underground city but they don't actually mention the name of the city. They video concludes by saying "authorities hope to open it to the public in 2018".
My question is where might I find more information out about this underground city?
Derinkuyu sounds like a possible candidate but the Google satellite imagry doesn't seem to match up with what's being shown in the BBC video.
Any ideas?