Essential Architecture-  Turkey

Saint Mary Diaconissa, Kalender Haneh Jamissi




Istanbul, Turkey






Brick, originally tile roof, later lead roof.


Present-day Mosque, former Church
The Church of Akataleptos ( Church of Diaconissa ) , The Kalenderhane Mosque
Kalenderhane Mosque (Turkish: Kalenderhane Camii) is a former Eastern Orthodox church in Istanbul, converted into a mosque by Mehmed 2.It has recently been identified as the church of St. Saviour Akaleptos.



Close to the eastern end of the aqueduct of Valens, and to the south of it, in the quarter of the mosque Shahzadé, is a beautiful Byzantine church, now known as Kalender Haneh Jamissi. It was visited by Gyllius, who refers to its beautiful marble revetment—vestita crustis varii marmoris—but has, unfortunately, nothing to say concerning its dedication. Since that traveller's time the very existence of the church was forgotten by the Greek community of Constantinople until Paspates discovered the building in 1877. But even that indefatigable explorer of the ancient remains of the city could not get access to the interior, and it was reserved for Dr. Freshfield in 1880 to be the first European visitor since Gyllius to enter the building, and make its interest and beauty known to the general public.


S. Mary Diaconissa. View of the North-west Side, taken from the Aqueduct of Valens.

S. Mary Diaconissa.
View of the North-west Side, taken from the Aqueduct of Valens.

S. Mary Diaconissa. The North Arm, looking east.

S. Mary Diaconissa.
The North Arm, looking east.


The identity of the church is a matter of pure conjecture, for we have no tradition or documentary evidence on that point. Paspates suggests that it may have been the sanctuary connected either with the 'monastery of Valens and Daudatus,' or with the 'monastery near the aqueduct,' establishments in existence before the age of Justinian the Great. It cannot be the former, because the monastery of Valens and Daudatus, which was dedicated to S. John the Baptist, stood near the church of the Holy Apostles close to the western end of the aqueduct of Valens. It might, so far as the indication 'near the aqueduct' gives any clue, be the sanctuary of the latter House, in which case the church was dedicated to S. Anastasius. But the architectural features of Kalender Haneh Jamissi do not belong to the period before Justinian. Mordtmann identifies the building with the church of the Theotokos in the district of the Deaconess, and in favour of this view there is the fact that the site of the mosque corresponds, speaking broadly, to the position which that church is known to have occupied somewhere between the forum of Taurus (now represented by the Turkish War Office) and the Philadelphium (the area about the mosque of Shahzadé), and not far off the street leading to the Holy Apostles. Furthermore, the rich and beautiful decoration of the church implies its importance, so that it may very well be the church of the Theotokos Diaconissa, at which imperial processions from the Great Palace to the Holy Apostles stopped to allow the emperor to place a lighted taper upon the altar of the shrine.


Theophanes, the earliest writer to mention the church of the Diaconissa, ascribes its foundation to the Patriarch Kyriakos (593-605) in the fourth year of his patriarchate, during the reign of the Emperor Maurice. According to the historical evidence at our command, that church was therefore erected towards the close of the sixth century. Dr. Freshfield, however, judging by the form of the church and the character of the dome, thinks that Kalender Haneh Jamissi is 'not earlier than the eighth century, and not later than the tenth.' Lethaby places it in the period between Justinian the Great and the eleventh century. 'The church, now the Kalender mosque of Constantinople, probably belongs to the intermediate period. The similar small cruciform church of Protaton, Mount Athos, is dated c. 950.' Hence if Theophanes and his followers are not to clash with these authorities on architecture, either Kalender Haneh Jamissi is not the church of the Diaconissa, or it is a reconstruction of the original fabric of that sanctuary. To restore an old church was not an uncommon practice in Constantinople, and Kalender Haneh Jamissi has undoubtedly seen changes in the course of its history. On the other hand, Diehl is of the opinion that the building cannot be later than the seventh century and may be earlier.


S. Mary Diaconissa. The Interior, looking north-east.

S. Mary Diaconissa.
The Interior, looking north-east.

S. Mary Diaconissa. The Interior, looking south-east.

S. Mary Diaconissa.
The Interior, looking south-east.


Architectural Features


The church belongs to the domed-cross type. The central area is cruciform, with barrel vaults over the arms and a dome on the centre. As the arms are not filled in with galleries this cruciform plan is very marked internally. Four small chambers, in two stories, in the arm angles bring the building to the square form externally. The upper stories are inaccessible except by ladders, but the supposition that they ever formed, like the similar stories in the dome piers of S. Sophia, portions of continuous galleries along the northern, western, and southern walls of the church is precluded by the character of the revetment on the walls. In the development of the domed-cross type, the church stands logically intermediate between the varieties of that type found respectively in the church of S. Theodosia and in that of SS. Peter and Mark.


The lower story of the north-western pier is covered with a flat circular roof resting on four pendentives, while the upper story is open to the timbers, and rises higher than the roof of the church, as though it were the base of some kind of tower. It presents no indications of pendentives or of a start in vaulting. The original eastern wall of the church has been almost totally torn down and replaced by a straight wall of Turkish construction. Traces of three apses at that end of the building can, however, still be discerned; for the points at which the curve of the central apse started are visible on either side of the Turkish wall, and the northern apse shows on the exterior. The northern and southern walls are lighted by large triple windows, divided by shafts and descending to a marble parapet near the floor. The dome, which is large in proportion to the church, is a polygon of sixteen sides. It rests directly on pendentives, but has a comparatively high external drum above the roof. It is pierced by sixteen windows which follow the curve of the dome. The flat, straight external cornice above them is Turkish, and there is good reason to suspect that the dome, taken as a whole, is Turkish work, for it strongly resembles the Turkish domes found in S. Theodosia, SS. Peter and Mark, and S. Andrew in Krisei. The vaults, moreover, below the dome are very much distorted; and the pointed eastern arch like the eastern wall appears to be Turkish. When portions of the building so closely connected with the dome have undergone Turkish repairs, it is not strange that the dome itself should also have received similar treatment.


In the western faces of the piers that carry the eastern arch large marble frames of considerable beauty are inserted. The sills are carved and rest on two short columns; two slender pilasters of verd antique form the sides; and above them is a flat cornice enriched with overhanging leaves of acanthus and a small bust in the centre. Within the frames is a large marble slab. Dr. Freshfield thinks these frames formed part of the eikonostasis, but on that view the bema would have been unusually large. The more probable position of the eikonostasis was across the arch nearer the apse. In that case the frames just described formed part of the general decoration of the building, although, at the same time, they may have enclosed isolated eikons. Eikons in a similar position are found in S. Saviour in the Chora.


The marble casing of the church is remarkably fine. Worthy of special notice is the careful manner in which the colours and veinings of the marble slabs are made to correspond and match. The zigzag inlaid pattern around the arches also deserves particular attention. High up in the western wall, and reached by the wooden stairs leading to a Turkish wooden gallery on that side of the church, are two marble slabs with a door carved in bas-relief upon them. They may be symbols of Christ as the door of His fold.


S. Mary Diaconissa. East End, North Side (lower part).

S. Mary Diaconissa.
East End, North Side (lower part).

S. Mary Diaconissa. East End, North Side (upper part).

S. Mary Diaconissa.
East End, North Side (upper part).


The church has a double narthex. As the ground outside the building has been raised enormously (it rises 15-20 feet above the floor at the east end) the actual entrance to the outer narthex is through a cutting in its vault or through a window, and the floor is reached by a steep flight of stone steps. The narthex is a long narrow vestibule, covered with barrel vaults, and has a Turkish wooden ceiling at the southern end.


The esonarthex is covered with a barrel vault between two cross vaults. The entrance into the church stands between two Corinthian columns, but they belong to different periods, and do not correspond to any structure in the building. In fact, both narthexes have been much altered in their day, presenting many irregularities and containing useless pilasters.


Professor Goodyear refers to this church in support of the theory that in Byzantine buildings there is an intentional widening of the structure from the ground upwards. 'It will also be observed,' he says, 'that the cornice is horizontal, whereas the marble casing above and below the cornice is cut and fitted in oblique lines.... The outward bend on the right side of the choir is 1112 inches in 33 feet. The masonry surfaces step back above the middle string-course. That these bends are not due to thrust is abundantly apparent from the fact that they are continuous and uniform in inclination up to the solid rear wall of the choir.'


But in regard to the existence of an intentional widening upwards in this building, it should be observed: First, that as the eastern wall of the church, 'the rear wall of the choir,' is Turkish, nothing can be legitimately inferred from the features of that wall about the character of Byzantine construction. Secondly, the set back above the middle string-course on the other walls of the church is an ordinary arrangement in a Byzantine church, and if this were all 'the widening' for which Professor Goodyear contended there would be no room for difference of opinion. The ledge formed by that set back may have served to support scaffolding. In the next place, due weight must be given to the distortion which would inevitably occur in Byzantine buildings. They were fabrics of mortar with brick rather than of brick with mortar, and consequently too elastic not to settle to a large extent in the course of erection. Hence is it that no measurements of a Byzantine structure, even on the ground floor, are accurate within more than 5 cm., while above the ground they vary to a much greater degree, rendering minute measurements quite valueless. Lastly, as the marble panelling was fitted after the completion of the body of the building, it had to be adapted to any divergence that had previously occurred in the settling of the walls or the spreading of the vaults. The marble panelling, it should also be observed, is here cut to the diagonal at one angle, and not at the other.


Apart from the set back of the masonry at the middle string-course, this church, therefore, supplies no evidence for an intentional widening of the structure from the ground upwards. Any further widening than that at the middle string-course was accidental, due to the nature of the materials employed, not to the device of the builder, and was allowed by the architect because unavoidable. Such irregularities are inherent in the Byzantine methods of building.


S. Mary Diaconissa. south eikon frame.

S. Mary Diaconissa.
South Eikon Frame.

S. Mary Diaconissa. Detail in the south eikon frame.

S. Mary Diaconissa
Detail in the South Eikon Frame

Plan of the Church.

Fig. 61.

 Longitudinal Section.

Fig. 62.

S. Mary Diaconissa, looking west.

S. Mary Diaconissa, looking west

S. Mary Diaconissa. Capital on column at the entrance to the Church.

S. Mary Diaconissa.
Capital on Column at the Entrance to the Church.

Text quoted from-
Byzantine Churches in Constantinople, Their History and Architecture.
MACMILLAN AND CO., Limited, London, 1912.
by Alexander Van Millingen and Ramsay Traquair and W. S. George and A. E. Henderson.