Nuruosmaniye Mosque

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.

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 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.

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.

Museum in a restored building that was the stables for Topkapı Palace. It exhibits various instruments for astronomy, clocks, pumps, weaponry and so on developed in Islamic realms down the centuries, but these are modern repro, and explanations of their context are skimpy. Islamic science and technology preceded that of Europe, as they insist, but they get the tone wrong, as if that was the triumphal culmination rather than the springboard for further advance.

Feshane began as a factory producing fezzes (fes), the red hats made of felt adopted by the Ottomans in the early 19th century as a part of westernizing efforts in lieu of much more traditional turbans. However, the fez was scrapped in favour of western garments during Atatürk's reforms of the 1920s and 30s as it was thought to symbolize the old, decidedly oriental regime. A restoration in 1998 made it a cultural and exhibition center, and after another in 2023, it was reopened as a culture and art center under the name Artistanbul Feshane.

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 contemporary art museum in a building converted from an old power plant: 1914-built and coal-fired, this was the oldest in Istanbul and the Ottoman Empire. Part of the plant was kept in almost exact original condition and now serves as the "Energy Museum".

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.

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.

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 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.

A resort on the Marmara coast. It's the westernmost part of Istanbul, between Çatalca and the province of Tekirdağ. There are some remnants of the Anastasian wall here, the scrappy ruins of a castle, an ancient cistern, the Piri Paşa Mosque, and Uzunköprü the long aqueduct.

The defining image of Istanbul, dominating the skyline with its great dome and six minarets. Completed in 1617 for Sultan Ahmed I, it's still a working mosque, so dress appropriately and avoid prayer times. Enter via the courtyard on the SW side. You step (shoeless) into the blue-tiled prayer hall beneath the main dome and its semi-domes. The mihrab is of finely carved marble, well-lit, and the minbar (pulpit) next to it is visible from almost all parts.