Kirmasti Cistern is a short distance north of the Fatih Mosque complex (site of the former Church of the Holy Apostles). The remains of this cistern are now 20 x 20 meters, with a height of 10 meters. It has 9 columns (3 rows of 3 columns) spaced 3.90 meters apart, but probably originally had 16 columns (4 rows of 4 columns). Only 3 of its original ionic imposts and capitals remain, with the other six replaces by concrete columns. It possibly dates to the 12th century.
İstanbul'da Bizans Dönemi Sarnıçlarının Mimari Özellikleri ve Kentin Tarihsel Topografyasındaki Dağılımı by Kerim Altuğ
“İstanbul'dan İki Arkeolojik Haber” by Haluk Çetinkaya