The always crowded Blue Mosque, which gives its name to the historical district of Istanbul, is one of the most important architectures to be seen in Istanbul. The Blue Mosque consists of more than 20 thousand Iznik tiles and these tiles are the reason why foreigners call "Blue Mosque". The only mosque of the Ottoman Empire with 6 minarets. Interesting fact is; the Muslim world is disturbed by the fact that the Blue Mosque is being replaced by the only mosque in the world with 6 minarets in the Kaaba. The sultan of that period had to build a 7th minaret for the mosque in the Kaaba.

Hagia Sophia is one of the most valuable structures in the world in terms of art and architecture. Considering its religious importance, one of the world's most valuable cultural assets emerges. Hagia Sophia is both the world's oldest cathedral and the world's fastest built cathedral. It still remains the 4th largest cathedral in the world today.

This building, which is remembered as the Bloody Church, also has an interesting story. They say; The Emperor has an illegitimate daughter and the Emperor marries her to the Mongol Han to make an alliance with the Mongols. Han died before they could get married. After Han's death, the girl returns to her father's side and has built this church. After she has it built, she dedicates herself to this church.

Neve Shalom Synagogue is the largest synagogues in Istanbul. Unlike other synagogues in Istanbul, the synagogue is very active, where Shabbat (Jewish rites), weddings, funerals, Bar Mitzvahs, Circumcision and religious holidays are held and also this build targeted by terrorist attacks in the past.