Bayazid is a huge market space, is one of the busiest places in town for several centuries. Popular name is Bayezid Square (Beyazit Meydani) but officially called
Freedom Square (Hurriyet Meydani). Ranks "Forum Tauri" forum Theodosiu Greek novel, the name coming from the bronze bull statue. It was a place of ritual sacrifice.
Here are some of the most beautiful buildings in the city - Beyazit Mosque, Istanbul University, Museum of calligraphy (which I have not seen).