The İskender Pasha Mosque is one of the historical mosques on Istanbul's Asian side. It is located across the Kanlıca Ferry Station, in a small square in the Kanlıca neighbourhood of the Beykoz district. Therefore, the İskender Pasha Mosque is also known as the Kanlıca Mosque. The mosque was commissioned by İskender Pasha and the entire design of the mosque belongs to architect Sinan. In the biography collections of architect Sinan, the mosque is mentioned as, the deceased İskender Pasha Mosque as well as the Kanlıca İskender Pasha Mosque. İskender Pasha, who was nicknamed Conqueror of Magosa, was a notable statesman and a judge of the army of the Ottoman Empire during the reign of Sultan Suleiman the 1st and Sultan Selim the 2nd. According to the epitaphs located on the sanctuary door, the construction of the mosque was started in 1590 and completed in 1560. The mosque was built in a classical Ottoman style. The mosque has a masonry shape as well, as it includes just one minaret. Also, the one minaret style is a rare property for a mosque and it can be seen in Architect Sinan's Piyale Pasha Mosque and Garabet Balyan's Küçük Mecidiye Mosque as well.
Throughout history, the mosque underwent several repairs. The mosque was repaired in 1895, 1910, 1926 and 1942. In the 19th century, outbuildings were added to the mosque, so the mosque actually became an Ottoman Social Complex. Sadık Rıfat Pasha, who was a notable person during the tanzimat reform era of Ottoman history, had a muvakkithane built as well. Muvakkithane is actually an earlier construction type found in mosques and literally means a place where a muvakkit – a person whose chief duty was to determine the time for ezan- works in. The muvakkithane was built just next to the mausoleum of İskender Pasha. In the mausoleum is where, İskender Pasha and his son Ahmed Pasha rests. Interestingly, the mausoleum is located at the North-side of the mosque, which is against the traditional Ottoman architecture. Therefore, the İskender Pasha Mosque can be classified in a group of mosques that have unique properties. After the construction of the muvakkithane, a schoolhouse-with a ground floor used as a coffeehouse- was built on the eastern side of the mosque almost within the same year that the muvakkithane was built. According to the rumours, there was a turkish-bath, which is as dead as a door-nail nowadays, associated with the İskender Pasha Social Complex. Architect Sinan mentioned this turkish-bath being built in his journal but he didn't mention the location where the Turkish-bath was built. Presently, the Journal of Architect Sinan is on display in the Turkish and Islamic Arts Museum. Also, Evliya Çelebi, an adventurer who travelled the entire territory of Ottoman Empire and some of its neighbouring lands in a period of over 40 years, had mentioned a Turkish-bath in the Kanlıca neighbourhood without giving the name of bath. Therefore, the existence of this Turkish-bath among the buildings of the İskender Pasha Social Complex is somewhat suspicious. According to those who believe in the idea of the İskender Pasha Bath's existence in Kanlıca, the building was destroyed in a fire in 1916. In 1925, the buildings of the social complex were severely damaged during the roadwork between the Üsküdar and Beykoz districts.