Ayasofya
The Basilica od St.Sophia, now called Ayasofya Museum, is unquestionably one of the finest buildings of all time. Built by Constantine the Great and reconstructed by Justinian in the 6th century, its immense dome rises 55 meters above the ground and its diameter spans 31 meters. You should linger here to absorb the building's majestic serenity and to admire the fine Byzantine mosaics. 

Ayasofya Museum

(Open every day except Monday).

      

Archeology Museum
The Archaeological Museums are found just inside the first court of Topkapi Palace. Included among the displays are the celebrated Alexander Sarcophagus among its treasures od antiquity. The museum of the Ancient Orient displays artifacts from the Sumerian, Babylonian, Assyrian, Hatti and Hittite civilizations 

(Open every day except Monday)



Archeology Museum
 
Rumeli Hisari or European Fortress, was built by Mehmet the Conqueror in 1452 prior to his capture of Istanbul. Completed in only for months, it is one of the most beautiful works of military architecture in the world. In the castle is the Open-Air Museum amphitheater that is the site for some events of the Istanbul Music Festival. (Open every day except Wednesdays)

Aya Irini

"Kasikci" diamond (Topkapi Palace)

Originally built as a kosk or pavilion by Mehmet the Conqueror in the 15th century, the Cinili Kosk, which houses the Museum of Turkish Ceramics, contains beautiful Iznik wares from the 16th century and fine examples of Seljuk and Ottoman pottery and tiles. (Open every day except Monday)

Like the Ayasofya Museum, the St. Irene Museum was originally a church. It ranks, in fact, as the first church built in Istanbul. Constantine commissioned it in the fourth century and Justinian later had the church restored. Reputedly the building stands on the site of a pre-Christian temple (Open ec-very day except Monday)

Across the street from the Ibrahim Pasa Palace is the Museum of Turkish Carpets which constain exquisite antique carpets and kilims gathered fromm all over Turkey. (Open every day except Monday)

 

Islamic Art
The dark stone building that houses the Museum of Turkish and Islamic Art was built 1524 by Ibrahim Pasa, grand Vizier to Süleyman the Magnificent, as his residence. It was the grandest private residance ever built in the Ottoman Empire. Today it holds a superb collection of ceramics, metalwork, miniatures, calligraphy, textiles and woodworks as well as some of the oldest carpets in the world (Open every day except Monday)
 
Near St.Sophia is the sixth century Byzantine cistern known as the Yerebatan Sarnici. Three hundred and thirty-six massive Corinthian columns support the immense chamber's fine brick vaulting (Open every day except Tuesday)
Yerebatan Palace

From the Mosaic Museum
The Mosaic Museum preserves in situ exceptionally fine mosaic pavements of the fifth and sixth centuries which remain from the Great Palace of the Byzantine emperors. (Open every day except Monday)
 
The Kariye Museum, the 11th century church of "St. Savior" in Chora, is after St. Sophia, the most important Byzantine monument in Istanbul unremarkable in its architecture, inside, the walls are decorated with superb 14th century frescoes and mosaics. Illustrating scenes from the life of Christ and the Virgin Mary, these brilliantly colored paintings embod the vigor of Byzantine art. Restored wooden houses in the area surrounding the church offer tea and coffe in a relaxed atmosphere far removed from the city's hectic pace. (Open every day except Tursday)

 Kariye  Museum

Mosaic from Kariye Museum
The Aviation Museum in Yesilkoy traces the development of flight in Turkey (Open every day except Monday)

The great field tents used by the Ottoman armies on campaigns are displayed in the Military Museum. Other exhibits include Ottoman weapons and the accoutrements of war. The Mehter Takimi (Ottoman militaryban) perform Ottoman martial music between 3:00 and 4:00 p.m. (Open every day except Monday and Tuesday)

 
The house in which Ataturk lived in Sisli now serves as the Ataturk Museum and displays his personal effects. (Open ever day except Saturday and Sunday).

In the Besiktas district the Naval Museum displays the great imperial caiques in which the sultans were rowed across the Bosphorus, as well as many other interesting exhibits of Ottoman naval history (Open every day except Monday and Thursday).

Also in Besiktas, the Museum of Fine Arts displays Turkish paintings and sculptures from the end of the 19th century to the present day  (Open every day except Monday and Tuesday).

Located within the gardens of Yildiz palace, the City Museum preserves and documents the history of Istanbul since the Ottoman conquest  (Open every day except Monday and Thursday). Also within the gardens are the Yildiz Palace Theatre and the Historic Stage Costumes Museum, with its richly decorated scenery and stage and its exquisite costumes.

Rahmi Koc Industry Museum, in the superb of Haskoy on the coast of the Golden Horn, an Ottoman-period iron -and steel- works building formerly called Lengerhane, houses industrial development exhibits  (Open every day except Monday).

  
Up the Bosphorus in the picturesque suburb of Büyükdere, the collections of the Sadberk Hanim Museum fill two charming 19th century wooden villas. A private museum, which originally displayed Turkish decorative arts, it has recently been expanded with a new collection of archaeological finds.  (Open every day except Wednesday).
 
For something different try the Caricature and Cartoon Museum in fatih on Ataturk Boulevard under the Bozdogan Aqueduct in the 16th century Gazanfer Aga Medrese. (Open daily 9:00 a.m. to 6:00 p.m.)