Blue Mosque (Sultanahmet Camii): Open daily from 09.00 till 1 hour before dusk. The mosque is closed half an hour before until half an hour after prayer time. On Friday the doors are closed an hour before until an hour after the noon prayer. Words aren’t enough to describe how beautiful it truly is on the inside.
Hagia Sophia (Aya Sofya) or Holy Wisdom: This is a former Orthodox Basilica then was turned into a Mosque and currently into a Museum. It is just across from the Blue Mosque and open daily between 09.00 and 17.00. Closed on Monday.