The magnificent Ulu Camii was built in 1399, when, to satisfy a promise to construct 20 mosques, Yildirim Bayazid chose instead to build a single mosque with 20 domes and minarets.

The next day, I look for the Chora Church, which Baha had suggested the last time I was here. His directions fail me so I hail a cab, but even the cabbie has trouble finding it. He drops me a few blocks away but points in the direction I need to walk to get there.

I locate the Ibrahim Pasa Palace, said to be one of the great surviving palaces in Istanbul dating to the Ottoman period. It's the home of the Islamic Art and Ethnology Museum.

This Ayasofya is among the oldest religious sites in the world, dating to 537 AD. It is also among the most important examples of Byzantine architecture still standing.

As Chief Architect, Mimar Sinan designed and restored 477 buildings and public works. The Suleyman Camii is regarded as one of his greatest achievements.

I hurry on to the Islamic Science Museum, eager to see how it compares to the Galileo Museum in Florence. There are globes in the entryway, but unlike the ones in Florence, these are not enclosed in glass...