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  ~Beth Yaakov Synagogue (Bet Yaakov Sinagogu)~

The Beth Yaakov Synagogue in Heybeliada was originally built in 1956 to accommodate the roughly 250 Jewish families that lived in the area since 1940. It shared a space with a Greek primary school for a short period of time before being converted into a full-time synagogue. It is no longer functioning.

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  ~Hagia Triada Greek Orthodox Church (Aya Triada Rum Ortodoks Kilisesi)~

Located on the western side of the Bosphorus are numerous Greek Orthodox churches, Hagia Triada being among them. It's large facade stands out against the crowded shops of Taksim and inside is even more ornate. Painted icons of saints and religious figures line the domed ceiling (Hagia Trirada is the first church that was allowed to be built with a dome after the fall of Constantinople, having been erected in 1880!) and gold adorns various relics and furnishings. The entrance is through side doors which can be opened by a custodian, but be mindful that there is an active congregation.

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  ~Tomb of Sultan Mehmed III (Sultan III Mehmed Türbesi)~

Located in the southern corner of the Hagia Sofia complex, the tomb of Sultan Mehmed III is home to 26 sarcophagi and a plethora of archeological marvels. The ornamentation of flowers, landscapes, and a star is somewhat different than other buildings typical for the time it was built in 1608, and inscriptions further detailing the tomb's history can be found engraved on the outside of the building.

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  ~Virgin Mary Greek Orthodox Church (Meryem Ana Rum Ortodoks Kilisesi)~

This Byzantine-era Greek Orthodox church originally opened in the 7th century, and houses icons dating back to the 1200s. It is rumored to be connected to the Hagia Sofia through a secret tunnel. As many churches and synagogues in Turkey, the worship site is no longer regularly in service and must be accessed by contacting the local attendant.