Hundreds of underground cisterns lurk beneath the surface of Istanbul, the largest of which is the Yerebatan Sarnıçı, or the Sunken Cistern. Built by Constantine the Great in the 4th century to provide water to his palace, it's survived the ages in remarkable form.
The beginning of our stay in Istanbul coincided with the beginning of March, and the slow onset of spring. The temperature was still cold, but blossoms were starting to appear on the trees and every day was milder than the last. And on the streets, we could sense the optimistic, expectant energy which always goes hand-in-hand with the end of winter.