Set in a fictional southeastern European country, and you see some domed buildings from time to time but no Orthodox temple. As far as I can tell, the drama avoids any mention of religion or religious differences between the peoples of said fictional country. (Though its population appears to be rather diverse.)

Time to plan a trip to Korea!

Posted by Soompi on Wednesday, April 6, 2016

Edit. 15.4.16
In the latest episode the Song Hye Gyo's character refers to the domed building as a chapel. I don't remember any interior shots of this "chapel."