Peaceful and active 16th-century Ottoman mosque in Saraçhane park, Fatih district. You can't miss…read moreit if you're here to see the Valens Aqueduct. It is most notable for its spiral minaret. Built in 1550 on behalf of Emin Nuretti Efendi, qadi 'asker of Egypt, it is named for its spiraling (burmalı) brick minaret, a copy of a Seljuq design that is unique in Istanbul. The mosque is not domed, but has a pitched porch, which rests on four reused Byzantine Corinthian stone columns. Unusually, the entrance is off-center behind a column. You can meet some nice cats here.

Unique Underground Mosque located in the alleyways near Karakoy harbor. The subterranean mosque…read morehouses the ancient tombs of martyrs near the back of the mosque. Thanks to Ensar of Istanbulday Tours for sharing this special site with our family.

The Greek Orthodox Patriarchy in Fener neighborhood is one of the sights that one should visit in…read morethe old part of the city. It's the core of the Orthodox world thus many Greeks come to visit the church. Each weekend they conduct mass and if you're lucky you may meet the Patriach himself as well. Don't forget to visit Fener and Balat neighborhood after/before your visit and get lost in the "old Istanbul".

With chandeliers and all interior design, the patriarchate has a very illuminating feel. Sacred…read morerelics and reliefs are kept here. The stone which was used to tie Jesus was brought there from Jerusalem. Since the 6th century the Phanar Greek Patriarchate has been the center of Orthodoxy. It was first founded by Constantine the Great in 330 AD. By the time Fatih Sultan Mehmed legalized the the Greek Orthodox Patriarchate after the conquest of Istanbul, Gennadios II was assigned as patriarch and he operated the patriarchate from the Apostles Church. The building was moved from one place to another several times.

When we arrived at the Basileus Hotel for our week in Istanbul, the staff suggested that my mom and…read moreI visit the Little Hagia Sophia. It is literally about a one minute walk from the hotel, so off we went. Emperor Justinian had this built as a church in the sixth century. Under the Ottomans, it was turned into a mosque. This structure and the Hagia Sophia are contemporaries, and have similar design, but neither is a model for the other. This mosque is a small one--you can stand in one spot in the room and see the full interior upon entrance. Still, it has the features you'll be used to seeing in other mosques, like the carpet designed to allow for worshipers to have proper spacing and be lined up for prayer. It also has very vibrant color on the interior and the windows let in beautiful light. It's not a site that takes much time to see, and I would not travel here if I was not in the area, but if you are nearby, a stop here wouldn't be out of order.

We decided to visit the "Little Hagia Sophia" (so called because it was also built by Justinian,…read morealong similar lines to the Hagia Sophia) before visiting some of the larger and more famous buildings. It is certainly less spectacular than the Hagia Sophia, but it has something to offer for people who are interested in older buildings. Do not expect original Byzantine architecture, however, as it has been heavily modified over the centuries, most recently to brace it against the vibrations from the railroad which runs right next to the building. For one thing, it is far less crowded, and you can take your time examining the paintings which decorate the upper galleries without feeling pushed or rushed. Although we did not have a language in common, the caretaker ensured that we saw all public parts of the building, by inviting us to climb to the gallery when we otherwise wouldn't have done so. As with all active mosques, you need to take off your shoes before entering, and women are asked to wear a headscarf. There were headscarfs you could borrow just inside the door. There is no charge to visit.