The architecture and art of medieval Greece .sx Byzantine church building .sx Leaving aside the sparse but picturesque remains of strictly Western church building in medieval Greece , as at Isova or Zaraka ( names in italics refer to sites discussed in the Entries ) , we are left with two principal building forms of the Byzantine world .sx The earliest and the simplest is the type known as a basilica , where a rectangular central hall or nave , usually separated from side aisles by rows of columns , and with clerestory windows and a wooden roof , has a projecting apse at the opposite end from that of the entrance ; it was normally approached through a colonnaded atrium , or open courtyard .sx Originating in pagan antiquity as an assembly hall , this is the basic form of early Christian basilica , and from its adoption for Christian worship in the fourth century it became standard practice to give it an east-west orientation .sx figure&caption .sx In size it could vary greatly , and the largest , a few of which still survive ( e.g. the church of the Akheiropoietos , Thessaloniki ) , were of great grandeur , many of them embellished with spectacular mosaics .sx By the later seventh century there were scores of buildings of this type on the Greek mainland , although only a few are still visible , and even fewer standing .sx In succeeding centuries the basilica design , when used for larger churches , seems to have been reserved mainly for those which were the seat of a bishop , and it was associated with this use ( as in the original building of the Mitropolis , Mystra ) into the later Byzantine period .sx It has been suggested that the conversion of the Parthenon in Athens to a church provided a model for this association .sx Early variations on the basilica form , besides the addition of further side aisles , could involve the insertion of a transverse aisle , or transept , close to the east end , and a porch , or narthex , across the west end .sx During the sixth and seventh centuries the grandest basilicas began to have a central cupola , as in the Basilica B , Philippi .sx In the middle and later Byzantine periods it was not common to build large new basilicas - those at Serres , Veroia and of the Koimisis , Kalabaka ( which in any case probably replaced an early Christian building of the same design ) , are unusual in their size .sx The great majority of basilicas built after the ninth century tend to be quite modest in size , and the absence of a cupola may be due for the most part to a simple shortage of funds ; the large number to be found at Kastoria or Veroia are mostly small or very small and must constitute a local exception , while those of Ag Khristoforos , Mystra and Ag Ioannis Khrysostomos , Geraki , are more typical .sx While the basilica form had links with antiquity , the second of the two Byzantine building forms was developed exclusively in the service of Christian architecture .sx Byzantine church building after the seventh century becomes overwhelmingly an architecture that exploits the dome .sx The basilica form was progressively superseded from the sixth century by a variety of designs which have in common a structure that is sufficiently strong to support a drum and cupola over an open , square space .sx The main centres for experimentation in these new designs would most probably have been in Asia Minor and in Constantinople itself , and there is still discussion as to where certain features originated .sx ( The supreme dome of the entire Byzantine period was always that of Ag Sofia , Constantinople , which was built between 532 and 537 , but the architects of this building are known to have come from Asia Minor .sx ) The drum could be supported either on the four wall sections abutting on to the crossing , on free-standing masonry piers , on columns , or ( very commonly ) on a combination of one or other system .sx In all cases the weight of the octagonal or circular drum , with the cupola above it , had to be transferred down to the four supporting members , and this was actually achieved by means of pendentives ; in their finest form these are a sophisticated piece of engineering in which a concave section of a sphere receives the weight of a quarter of the drum on its upper section and passes it down to the single member ( pier , column or wall section ) out of which it is built .sx The most common solution to this problem throughout all of Greece became the so-called 'inscribed cross' or 'cross-in-square' plan , and this was in common use by the eleventh century .sx It involved the dome over the central square space of the naos being supported either on four columns or , very commonly , on two columns and the two wall sections either side of the main apse ; to north , south and west there were usually barrel vaults , with often a fourth one to the east adjoining the apse .sx On the plan the dome and its adjacent vaults thus appear as 'inscribed' within an approximately square outer space .sx There are many possible variations on this ; these include greater or smaller depth of lateral barrel vaults , the insertion of buttressing semi - domes on eastern and western sides of the drum , extending the western bay to enlarge the space of the naos , inserting galleries in the crossing and thus adding a second storey , and so on , but the one constant factor remained the emphasis on the central dome .sx figure&caption .sx At an early stage further spaces were added , such as the two subsidiary apsed chambers built either side of the main apse ; these became standard in most churches , and are called the prothesis and diaconicon ; only the smallest churches might not have them .sx Almost invariably the inscribed cross design incorporated a narthex to the west , with sometimes a second , or exonarthex , as well , and larger churches often had a gallery above this .sx Further domes could also be added - either one over the bema , or over narthex and gallery , or four more over each of the four corner bays .sx Indeed , either the multiplication of domes , or the expansion of the central dome to exceptional diameter or height , became the chief ways in which builders or patrons could express the importance of a new church ; such expression was otherwise left to lavishness of patterns in exterior brickwork , richness of interior decoration in the carving on capitals and templa , and to colourful frescos or mosaics on the upper surfaces of the building .sx In some , less usual , cases there was experimentation with the use of further apsidal forms ( or absidioles ) to north and south , and even to the west as well ; examples of this are the churches of Ag Apostoloi , Athens ( Agora ) , the original form of Ag Andreas , Peristera and the katholikon of the monastery at Molyvdoskepastos .sx Such apsidal forms provided a more varied exterior profile , with inside a more fluid and varied spatial quality .sx Far more common , as a way of imparting individuality to the exterior of churches , was the use of brick ornament ; this could be quite restrained , as in the ubiquitous form of string courses of bricks set with projecting corners to produce the 'dog-tooth' effect , or more lavish and varied as at Elassona or Gastouni , or they could be set in blind arcades or niches .sx This ornament is never found inside , as interiors were completely covered by carefully developed didactic programmes of decoration in fresco or mosaic , as we shall now see .sx Byzantine artistic practice .sx Over the centuries the Byzantines developed an approach to imagery markedly different from that prevailing in western Europe .sx Mainly codified before and during the period of Iconoclasm ( 726-843 ) , it involved the concept of an image , when created in the correct way , being a receptacle for the spirit of the person or subject it portrayed .sx For the Byzantine beholder , an image , or icon , was not just a likeness of a saint , but contained the essence of the prototype , and so actually was the subject portrayed .sx Other factors followed from this .sx If by reason of the life he or she had led while in the world , a saint was worthy of veneration , so the image of the saint was equally worthy ; one of the church fathers had already written in the fourth century :sx " Honour paid to the icon passes on to the prototype " .sx To pay honour and respect to a person must involve some form of communication , and so the iconic image is invariably shown in a frontal pose ( or nearly so ) and with the eyes open .sx To portray a figure in a way in which the beholder could not communicate with it would have been pointless as it could not have been 'understood' .sx The Byzantines had a strongly hieratic view of the universe , and this too was clearly expressed in their art .sx Just as the most sacred subjects , such as the feasts of the Dodecaorton , are of greater sanctity than lesser episodes of Christ's life , so images of these feasts are also more venerable .sx A hierarchy of sanctity grew up as a product of this outlook , and the most complete expression of the Byzantine view of the Christian universe became the extended sequence of images that can be found in a Byzantine church .sx The image of the most venerable of all subjects , Christ Pantocrator , can usually be found in the highest part of the church building - the summit of the cupola ; below this are often found adoring archangels .sx The dome of the church becomes identified in this way with the dome of heaven .sx The second most sacred part of the church , the main apse , houses the next most holy of images - that of the Mother of God .sx Either some of the feasts of the Dodecaorton , or else the four evangelists , can then be found in the four pendentives supporting the cupola ; below these , in the soffits of the arches and in wall niches and subsidiary vaults , are usually images of single saints from the service books of the orthodox church .sx The image which displays the church's dedication can often be found on the north wall adjacent to the templon .sx On the lowest wall areas there was either a cladding of marble sheets , often decoratively cut to form symmetrical patterns ( as at Osios Loukas ) , or more commonly , plaster painted to imitate marble ; this was ultimately a continuation of an antique Roman practice .sx It should be emphasized that complete uniformity can never have been intended ; no two church interiors are ever identical , but there are enough features in common to demonstrate the existence of a general approach .sx It has even been suggested that the marriage of the architecture with the imagery that it housed became so intimate that it is difficult to visualize one without the other ; certainly some form of close collaboration between builders and painters or mosaicists must have existed for such a perfectly integrated concept to have become established .sx It was also within this context that the use of portable icons was established from earliest times .sx Today icons will be found in large numbers on later decorative wooden iconostases , but the custom of displaying in some special way icons of particular significance , some perhaps relating to the dedication of the church , is probably quite an early one .sx The practice of kissing icons , which is still universally observed , also certainly has early origins .sx The modern visitor to a Byzantine church should be aware that the forms of the building in which he finds himself were developed in partnership not just with the imagery that they contain ; they would also have grown up in answer to liturgical needs , and can to this extent be assessed on purely functional grounds .sx The orthodox liturgy , although subject to modification and adaptation , from early days took on certain formal needs which remained fairly constant .sx In later centuries new demands also arose which needed to be accommodated ; the rite of baptism for example , had been very important in the early church , thus necessitating a baptistry building ( as at Amfissa) .sx This sacrament was given less emphasis as the centuries passed , and separate baptistries were not built , but it was revived towards the end of the Byzantine period , and started again to have its own accommodation , usually in part of the narthex .sx