Aya Sofya
After decades in which scaffolding cluttered the interior of Emperor Justinian's sixth-century Byzantine masterpiece, the thrill of being able to experience the extraordinary spaciousness of this famous church-turned-mosque-turned museum is hard to overstate. Downstairs the building is largely empty; the best of the glittering mosaics lurk in the galleries upstairs. Newly opened are the tombs of several early Ottoman sultans and their slaughtered sons – before primogeniture new sultans immediately had all potential rivals killed. Before the end of the year, the city's finest carpets will go on display in the soup kitchen added after the church was turned into a mosque.