Hagia Sophia (Aya Sofya), Istanbul

Address Hagia Sophia, Istanbul Map,

Hagia Sophia was the largest church in the world until the Cathedral in Sevilla was built, and it's dome served as a model for many other buildings, including the Blue Mosque.

While you'll take Hagia Sophia at a faster pace with kids than you might otherwise, it can still be enjoyable. Ramps connect the lower and upper floor, and you should be able to push a jogging stroller right up the ramp. With a walking child, you might play these up as a secret passage to be explored (it worked for us).