Çilingoz Nature Park

This attractive neighbourhood was home to a large Christian and Jewish population until some decades ago and still has a number of sights like two synagogues, some churches among which the Armenian Surp Krikor Lusavoriç, dozens of wooden houses and a Jewish and Christian cemetery.

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.

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.

The Church of Theotokos Pammakaristos ("All-Blessed Mother of God") was built between the 11th and 12th centuries. The parekklesion or side-chapel was added maybe 1300, with rich mosaics. The main building became a mosque in 1591, named for Sultan Murad III's conquest (fetih, hence Fethiye) of Georgia and Azerbaijan: the interior was opened up, but the chapel was undisturbed and in modern times became a museum. In 2020 the entire building was proclaimed a mosque, and every scrap of Byzantine artistry was covered up, so now there's nothing worth seeing.

Although not at the size of Hagia Sophia, this is the largest active church in Turkey. It’s directly on Istiklal St, but somewhat hidden from view by its yard portal. Catholic Masses in Italian, Turkish, and English (in different days of the week).

Dedicated to toys, this is a museum which adults can enjoy as much as kids. It's founded by poet Sunay Akın, and is housed in a historical mansion in the Göztepe neighbourhood east of Kadıköy. Among the 2,000 pieces of toys from around the world in exhibition, the oldest are a French-made violin from 1817 and a U.S.-made doll from 1820.

Vast underground cistern built by Justinian in 532 to store the city's water, the largest and best-known of the hundreds constructed. It's a cathedral-like space with 336 richly decorated columns. Time was you explored in a little rowing boat, but tourist numbers have soared and water levels have dropped, so now you follow a boardwalk, with lights, piped music and art installations. It's sometimes a film location, and stages concerts. But the crowds rob it of atmosphere and you might prefer to seek out one of the less-visited cisterns.

A neighbourhood east of Şişli known for its Art Nouveau apartment buildings, the ground floors of many of which are upmarket restaurants, cafes, pubs, and garment stores lining the sidewalks. Nobel laureate Orhan Pamuk, well-known Turkish novelist, is a lifelong resident of the neighbourhood which formed the background of several of his novels.

Tiny house museum on the life of Turkish novelist Orhan Kemal (1914–1970).

The third and grandest of the churches on this site, completed in 537 AD. The 30-m diameter dome covers what was for over 1000 years the largest enclosed space in the world, only surpassed in 1520 by Seville cathedral. It used "pendentive" architecture to throw the dome's weight onto four stout pillars, a design that inspired many Eastern Orthodox churches and Ottoman mosques. It became a mosque after the Ottoman conquest in 1453, remaining so until 1931. It was then a museum until 2020 when it was again proclaimed a mosque. That means you must work around prayer times and dress appropriately.

The imperial enclave of the Ottoman emperors for four centuries. Lavishly decorated, with exhibitions of fine craftmanship and four courts of increasing grandeur. The second court has the Harem and the State Treasury, housing a weaponry display. The third court has the Imperial Treasury, with Islamic and Christian relics. The views from the Fourth Court over the Bosphorus are spectacular. Reckon on spending several hours here and bring water as the museum kiosk is overpriced.

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.

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.

This is a 1927 Beaux Arts building named after its patron Süreyya İlmen Pasha, then a deputy of Istanbul who was impressed by theatres in Europe during his visits. It became the first opera house in the Asian side of Istanbul, but due to deficiencies in its interior design, it barely staged any opera and was converted to a cinema soon afterwards. It underwent a significant restoration and reverted to its original purpose in 2007, so now houses performances of ballet, opera, and classical music; good tickets are often extremely cheap.

This lavish palace with 285 rooms and 43 halls was the admin centre for the Ottoman Empire in its last 60 years. The palace government block (Selamlık) includes the Imperial Mabeyn (State Apartments) and Muayede Hall (Ceremonial Hall), while the Imperial Harem was the sultan's private quarters. Also here are the Painting Gallery, Music Museum, Clock Museum and Museum of Palace Collections. Free audio guide in several languages available by the ticket office. No photography inside, no backpacks but you can leave them in the cloakroom. Allow 3 hours to see everything.

This is a completely wooden building rising up to six storeys. It is said to be the second largest wooden construction in the world and the first in Europe. On the second highest summit of Büyükada (İsatepe, "Jesus hill", 164 m asl), it lies abandoned and dilapidated amidst the pine woods, like a picture-perfect haunted manor. It was built in the late 19th century, originally intended as a luxury hotel for the passengers of the Orient Express but never served that purpose and was put in use as an orphanage by the Greek community until it was closed down in 1964, within the context of the deteriorating Turkish-Greek relations due to the Cyprus dispute. It's dangerous, not to say forbidden, to enter the building due to the damages inflicted by decades of neglect. The title holder is the Ecumenical Patriarchate, led by Bartholomew I who wants the building restored and made a global environmental research centre (he's known as the "Green Pope" due to his efforts for environmental protection), but given the long legal disputes on titleship, not to mention the enormous funds required to bring the building to life, don't hold your breath.

The Greek Orthodox church is on the highest summit of the archipelago, Yücetepe ("great hill") at 203 m asl. Walk up from Birlik Meydanı for about 35-40 min; the cobbled incline is too steep for a bicycle. The church building is unexceptional, but the backyard has a great view of the other islands and the sea. St George's day is celebrated here annually on Apr 23, when you can expect tens of thousands attendees willing to make wishes — if you want to skip the crowds set off before 06:00 or else you will be standing for a long time until you are let inside by the police in groups of 10–15 people at once. Wishmaking rituals range from usual candle burning, to slightly more unusual climbing up to the church on bare feet, to very curious untying wool balls all along the path leading there. If you are interested to partake, you will meet lots of vendors selling candles on the streets that day, right as soon as you step out of the ferry, but it's best to have them from the church for a donation. In case you are wondering if all of Turkey's dwindled Greek Orthodox minority are there that day, or if the community is even that populous, no, most of the visitors eagerly waiting for a blessing from the priest are non-Christian Turks, but there is nothing surprising about that: this is Turkey, where the east and the west meet, and cultures truly mix.

A historic 3-storey house, easily distinguishable among the modern apartment buildings thanks to its brightly coloured and gracefully decorated exterior. This is where the future founder of the Turkish Republic, Kemal Atatürk rented in 1919 while staying in Istanbul before setting sail to Samsun on the Black Sea coast to start the Turkish War of Independence. Hosts Atatürk-related paraphernalia and photos.

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.

Built circa 1200 as the Eastern Orthodox Theotokos Kyriotissa Church, after the Ottoman conquest it was handed over to the Qalandari, a Sufi sect. In the mid-18th century it was converted to a Sunni mosque, and its mosaics were plastered over. The original appearance was restored in the 1970s.