Hagia Sophia stands as the third and most magnificent church built on its historic site. Completed in 537 AD, its grand architecture has amazed visitors for centuries. The enormous dome, measuring 30 meters in diameter, once sheltered the largest enclosed space in the world. For over a thousand years, no other building matched its scale—only in 1520 did Seville Cathedral surpass it.
The unique design of Hagia Sophia uses "pendentive" architecture, a groundbreaking method at the time. This technique shifts the massive weight of the dome onto four strong pillars, allowing the vast, open interior space. The success of this design influenced countless Eastern Orthodox churches and later, Ottoman mosques throughout the region.
Hagia Sophia’s purpose and atmosphere have changed with the tides of history. After the Ottoman conquest in 1453, the building became a mosque and remained so until 1931. It then served as a museum for nearly nine decades. In 2020, Hagia Sophia was once again designated as a mosque. Visitors today are asked to be mindful of prayer times and to dress appropriately during their visit.
Source - https://en.wikipedia.org/wiki/Hagia_Sophia
The Golden Gate was the ceremonial entrance through the Theodosian city walls. After the Ottomans captured the city in 1453, Mehmed II needed a stronghold for his treasures and documents. The gate was therefore bricked up and the walls reinforced into a fortress, with valuables stored in its seven towers, hence yedi kule. In the following century the treasury moved to Topkapi Palace and the fort became a prison for high-level detainees - Osman II was strangled here in 1622. It remained in use until 1837, whereupon the Golden Gate was re-opened.
A ritual dancing hall of the mystical Mevlevi order, the followers of the teachings of Mewlānā Rumi. The quiet and peaceful garden is a welcome escape from the hustle and bustle of Beyoğlu. The oldest Mevlevi lodge in Istanbul, the convent was started in 1491, when the surrounding area was, hard to believe today but, pure wilderness beyond the city walls of Galata, although the current building dates back to 1855, as the older versions succumbed to repairs, rebuildings, and fires. However, the lodge was shut down in the early years of the republic (in 1925) along with all other 'reactionary' movements in Turkey, and the building has been serving as a museum dedicated to the Mevlevi order since 2010. Downstairs is a series of rooms dealing with the daily life of an average dervish, with informational signs in Turkish and English about the history of Islam and the Mevlevi order (also notice the original wooden pillars that support the building on this floor). On the upper floor is a dancing hall, a perfect example of 19th century Ottoman Baroque. Pre-Covid, this was where the sema whirling ceremonies were held every weekend evenings (admission by an extra ticket costing around 100 TL); check if they resumed. On the third floor is a display of various traditional Turkish/Islamic arts, including paper marbling (ebru), and calligraphy. After exiting the building, check out the small graveyard (or the "silent house" as the sign at its entrance says) on one side of the building, shaded by a number of hackberry trees, which Ottomans favoured to plant in the yards of mosques and graves to sign holiness. Here, the carved fez, or the basket of flowers in case of women, perched upon the highly detailed marble gravestone indicates the occupant's rank in the dervish hierarchy. At one corner of the necropolis is the grave of İbrahim Müteferrika, a converted Hungarian who was the first to start automated publishing in Ottoman Turkish in the 18th century, and served as the translator of Hungarian revolutionaries who sought asylum in Turkey, such as Kossuth, who stayed for a year in Kütahya, or Ferenc Rakoczi, who lived his last years in Tekirdağ.
Turkey was slow to protect its antiquities and to display them properly, but in 1867 Sultan Abdülaziz toured the museums of Paris, London and Vienna and saw what was needed. The main collection is in a grand neo-classical building of 1891, with two annexes for ancient art and Islamic art. Exhibits include Sumerian tablets, pieces of the wall of Babylon, Roman statues, and the sarcophagus of Alexander the Great, which he never lay in.
A historic house museum dedicated to the life of Adam Mickiewicz, renowned Polish poet. This is where he lived while in Turkey from September 1855 to 26 November 1855, when he died of illness.
Istanbul's former Asia-side railway station nowadays has no trains, but is worth a look. It was built by the Germans in 1908 in a distinctive Teutonic-castle style - to make an impact on travellers from Asia about to step into Europe, and a counterpoint to Sirkeci station (also closed) on the European side which is modelled in Oriental style. It's intended eventually to make this the terminus for the high speed rail network.
A small town 40 km west of central Istanbul and 15 km north of Büyükçekmece that had a substantial Greek population until the 1920s transfers. Spared from destruction in the Balkan wars which foreshadowed the Great War, the old quarter has many historic wooden buildings and fountains in leafy squares. A short stretch of the old town walls still stand just north of the centre. In the outer areas, bunkers of the WW2 'Çakmak Line' and remnants of the Byzantine Anastasios Walls could be observed. The town's main sight, housed in a red brick neoclassical building erected as a Greek tavern, this museum commemorates the forced population transfer of 1922–26, whereby Greeks living in Turkey were expelled to Greece, while the Turks of Greece were expelled to Turkey.
Completed in 1851, this houses a mantle said to have been worn by the prophet Muhammad. The mantle is displayed during Ramadan.
On top of a hill overlooking the Golden Horn, this is a magnificent mosque built by Sinan in the 1550s. It was centrepiece of a large külliye, a religious complex which included madrasas, a public kitchen and a hospital.. The small cemetery east has the mausoleums of Suleiman the Magnificent and of his wife Hurrem Sultan or Roxelana.
A charming domed church built in 1880 at the side of Taksim Square, now uneasily contesting with Taksim Mosque for being the main landmark of the southern edge of the square.
Built in the early 5th century as a monastery dedicated to Saint Andrew the Apostle, in 766 it was the burial place of Saint Andrew of Crete and was later re-dedicated to him. It was rebuilt in the late 9th century and again in the 13th, then around 1490 converted into a mosque. From the 16th century it was occupied by the Dervishes, when the legend arose that a chain hung to a cypress tree in the courtyard was a truth diviner. The chain was swung between rival witnesses and the one it hit was telling the truth. The cypress stump is still standing.
Built in first half of the 15th century, this is the large medieval castle under the Second Bosphorus Bridge. Its former name Boğazkesen (Turkish)/Laimokopia (Greek) means both "strait-blocker" and "throat-cutter" in both languages and denotes the reason of its building—to shut the supply routes from the Black Sea in the north into the slowly falling apart Byzantine Empire through the Bosphorus. Rumeli, literally "the Roman land", was the name of the European half of the Ottoman Empire, and as is usual with some other structures and villages along the Bosphorus, used as a prefix to differentiate Rumeli Hisarı from its counterpart in the Asian Side, the much smaller Anadolu Hisarı just across the Bosphorus.
The Byzantines built several great palaces in Constantinople and this is the only one to survive almost intact. It's from the late 13th century, in typical alternating marble and red-brick rows, and was an imperial residence: Porphyrogenitus means "born to the purple" indicating the heir to the crown. Yet it was merely an annex or pavilion within the much greater Palace of Blachernae, of which nothing else remains. It's set within the north end of the Theodosian Walls and was much bashed during the Ottoman capture. Later it was variously a menagerie, brothel, pottery, poorhouse and bottle works, then fell derelict in the 20th century. In 2021 it re-opened as a museum.
Chora means countryside, and when built as a monastery in the 4th century it stood outside the Constantine walls; a century later, it was incorporated into the Theodosian walls. It was rebuilt in the 11th century then wrecked by an earthquake, so the structure and fabulous mosaics you see now are 14th century. When the church was converted to a mosque in 1500 the mosaics were plastered over, and only restored in 1958 when it became a museum. In 2020 it was again proclaimed a mosque but here (unlike Fethiye Mosque) they saw the sense and tourist income of preserving the mosaics. You need to work around prayer times.
A remarkable Bulgarian Orthodox church better known as Demir Kilise, "Iron Church", as it's a cast iron prefab. The Bulgarians split from the Greek Orthodox and established their own wooden church in 1870, which burned down. The ground was too weak for a masonry or concrete structure so they opted for cast iron. The sections were cast in Vienna, shipped here and assembled, to open in 1898. The church was renovated in 2018, but the archpatriarchate building across the street remains a gaunt shell.
This is a triple structure: the church of the Monastery of Pantokrator built 1118, then a public church circa 1136 plus a chapel that served as a royal mausoleum. It became a mosque and medresse in Ottoman times, but without massive alteration so it's a prime example of middle-Byzantine architecture. It's nowadays again a mosque, photogenic by day or dusk but the area should be avoided at night.
Opened in 2012, this museum is unique and a must-see when you are in the Beyoğlu area. It was created by Turkish Nobel laureate Orhan Pamuk alongside a novel of the same name. It tells the love story of the two main characters from the novel, and represents life in Istanbul during the late 1970s to early 1980s, as it exhibits thousands of objects from that era.
A neo-gothic Anglican cathedral which would not be out of place in northwestern Europe, the Crimean Memorial Church was built for the Protestant community of the city by Britain in the late 19th century. It was named in honour of the soldiers died in the Crimean War of 1856, fought against Russia by the allied Ottoman and British Empires. The congregation of the church today mostly consists of Anglican East Asians and Sri Lankans resident in Istanbul.
Started in 1613 by the Ottoman sultan Ahmet I (r. 1603–1617, who also had the Blue Mosque in the Old City built), and extensively renovated by the art-loving Selim III (r. 1789–1807), this sole building, which itself has the distinction of being the only intact structure that dates back to the rule of Ahmet III (r. 1703–1730), set inside a beautiful garden of pools and mature cedar and magnolia trees is the only remaining part of what was once the fourth largest palatial complex in Istanbul, extending all the way to the banks of the Golden Horn (which is now occupied by the derelict buildings of the closed shipyard, which also block part of the view towards the shore). According to the local rumour, its name (which in Turkish means "mirrored poplar") derives from the now absent mirrors gifted by Venice to the palace that were presumably "as tall as the poplars" (aynalar kavak). The highly decorative and colourful interior includes several rooms of original furnitures fit for a sultan, some of which are covered with nacre, and walls embellished with Ottoman poems praising the palace and Selim III. Downstairs is a small museum dedicated to music, which exhibit some of the instruments (violins, ouds, and kamanchehs) and gramophone records owned by Fatma Gevheri Sultana (1904–1980), the granddaughter of Abdülaziz I (r. 1861–1876). While you are outside, also check out the old main entrance (now closed) towards the Golden Horn, topped by a dome. Worth the half hour spent there.