Sinasos, nowadays called Mustafapasa, was sort of unofficial "capital" of the Greek population of Cappadocia, once upon a time. The Orthodox/Greeks that had been living for centuries in that region, where sent to Greece in 1923-24, being part of the exchange of populations between Turkey and Greece, according to the Treaty of Laussane. The same thing happened the other way around, with the Muslim/Turks that had been living for centuries in Greek Territory, which took the road to Turkey. Many of the Greeks living in Turkey, were only Turkish-speaking and when they came to Greece they were received with suspicion and depreciative characterizations and the same thing happened in Turkey, with many of the Turks that were only greek-speaking.
More than half of the Greek population of Cappadocia were Turkish speaking (but they wrote the Turkish language with greek characters, a "language" often called "karamanlidika"). The rest of them were speaking both languages, Turkish and Greek, among them the most "clear" Greek, could be heard in Sinasos, a small town with great economic and cultural development, especially in the 19th century. Around that time its population was about 4.000 people (3.500 Greeks).
The Greeks of Sinasos, were successful merchants in Istanbul, located around Galata, where they controlled much of the fish market. They had the exclusive rights to sell Russian black caviar, thing that made many of them very rich. The never forgot their homeland, sending back money, "investing" in luxurious mansions and establishing 3 Greek schools. When they were reaching around the age of 45-50, they were returning to Sinasos to enjoy the "fruits" of their work, their beautiful houses, leaving their jobs in Istanbul to the hands of their sons.
You can see many of the old Greek mansions, if you visit Sinasos (Mustafapasa) today. All of them have beautiful, carved and decorated doors.