This yalı belonged to Mahmud II’s kahvecibaşı (head coffee-maker), Kânî Mustafa Bey, who wrote a famous treatise on archery. It was originally three times the size and featured three sections: the harem, the selamlık and the boat house. It was built on the ruins of a Byzantine monastery and its ayazma (sacred water source) is still in the garden. In 1848, it was purchased by Zarif Mustafa Pasha. The imposing building is still in good nick and is one of the most expensive yalıs in Istanbul, estimated to be worth $70,000,000.