Sultanahmet Square: Hippodrome of the Roman-Byzantine Empire, Racetrack of the Ottoman Empire. The Sultanahmet Square, which witnessed various colorful entertainments and historical events throughout history, is the most known and visited square of Istanbul with the Blue Mosque in a corner, the Ibrahim Pasha Palace in a corner, the Hagia Sophia in a corner and the Topkapı Palace in another corner. The Sultanahmet Square, which is the favorite location for Ramazan entertainments and travel groups, will host the Solo Exhibitions of the Yeditepe Biennial.