This is the 6774th most frequent Korean word.
이스탄불
"Istanbul" (a city in Turkey).
Here, '이스탄불' is used as a proper noun referring to the city itself.
이스탄불은 터키의 가장 큰 도시입니다.
Istanbul is the largest city in Turkey.
In this sentence, '이스탄불' represents the location where the action (experiencing cultures) took place.
나는 이스탄불에서 여러 문화를 경험했어요.
I experienced many cultures in Istanbul.
'이스탄불' is utilized as an attributive noun indicating that the architecture belongs to or is associated with Istanbul.