Hippodrome-The center of sport activities in Constantinople, capital of the Byzantine empire, today named Sultanahmet Meydani, with its four monuments; The German Fountain of Wilhelm II, Egyptian Obelisk, Serpentine Column (Spiral Column). Blue Mosque (Sultanahmet Mosque)-Built by the architect Mimar Sedefkar Mehmet aga. Until 19th century was the traditional point for the pilgrimage to Mecca(on Friday visit is not allowed because of Friday prayers). Hagia Sophia Museum-The best known Christian church in Turkey, one of the greatest marvels of architecture, which was constructed as a basilica in the 6th century by Emperor Justinian (St. Sophia is closed on Monday). Grand Covered Bazaar-The most attractive shopping Centre in the world, with nearly 4000 shops, selling antique, jewelry, gold, carpets, leather wear and souvenirs (Grand Bazaar is closed on Sunday).