1. General

Nesebăr, previously known as Mesembria, is located on the west coast of the Black Sea 14 km southwest of cape Emona and 27 km northeast of the city of Burgas in Bulgaria. The ancient part of the town is situated on an island 850 m long and 350 m wide and occupies an area of 25 ha. It is connected to the mainland by a narrow man-made isthmus 400 m long (Fig. 1).

The geographical location predestined to a great extent the role played by Mesembria in the ancient and medieval history of the West Black Sea coast. On the one side, the location of the ancient city on the sea route and parallel land road linking Byzantion/Constantinople with the Danube delta defined Mesembria as an important harbor and commercial center throughout the centuries.¹ On the other side, the advantages of the peninsula for natural defense improved by a circuit fortress wall turned the city into a cornerstone of the strategy of defense and control over the west coast of the Black Sea for any of the rivaling powers from the Late Roman period until the time of the Ottoman conquest.

Chronologically, the surviving medieval monuments in Mesembria belonged to three main periods: the Early Byzantine period (5th -6th c.), the 11th c., and the 13th -14th c. Not surprisingly, the majority of them are churches yet one may note other interesting and important elements of the material culture of the medieval city either.

2. The walls

The earliest walls of the settlement were built by the Thracians in the 8th c. B.C. Their remains supplied with a gate constructed of rubble fitted with mud have been attested along the northwestern coast of the peninsula. The fortification of Mesembria, however, was not a primary concern for the Dorian Greeks who founded a colony there in 510 B.C. As late as the end of the 5th c. and until the 3rd c. B.C. they have attempted the construction of a new fortress wall. The surviving sectors in the western part of the ancient city reveal a construction of facing of regularly arranged large stone blocks closely fitted together and a core of rubble and earth. In fact, that wall defended Mesembria throughout the entire Roman period either.

In the course of the large scale construction program attempted by Anastasios I (r. 491-518) Mesembria was reinforced with new walls constructed in opus mixtum. In now days sectors of the Early Byzantine walls preserved to a height of 8 m can be seen along the southwestern coast and southeast of the peninsula 80 m far out at the sea. The main gate of the Early Byzantine fortress arranged against the isthmus is also one of the fortress’ structures that survived in a relatively good condition (Fig. 2). It is arranged in accordance with the Roman tradition protected by two flanking rectangular towers symmetrically to which were arranged semicircular and circular towers (Fig. 3). They projected 11.80 m in front of the curtain which made them very effective in active defense. The towers were vaulted and poternas were cut in their lateral walls.²

The earliest reconstruction of the fortress is dated to the time of Justinian I (r. 527-565).³ Then, following the Avar attack in AD 587, repairs of the walls were attempted at the end of the 6th and beginning of the 7th c (Fig. 4).⁴ An inscription on three marble slabs found in Mesembria notes a restoration of the city “from its foundations” by Basil I (r. 867-886). Indeed, some of the repairs of the city walls accomplished with bricks are dated to the last quarter of the 9th c. and might be related to the rebuilding activity of Basil I between AD 879 and 886.⁵ The next repairs have been also recorded by an inscription referring to the emperor Constantine X Doukas (r. 1059-1067) and his wife Eudokia.⁶ The last reconstruction works on the fortresses walls are dated to the first half of the 14th c.⁷

3. The Early Byzantine baths

The thermae are situated in the lowest northern part of the peninsula to the northeast of the church of St John the Baptist. They consisted of an apodyterium, central hall and three heated rooms supplied with basins yet the entire arrangement of the baths cannot be completely restored since a part of them remained under the foundations of a modern building (Fig. 5). The walls were marble faced on the interior. The central hall was either domed, or covered by a groin vault as evident from the four columns placed there. Built in the 5th -6th c., the thermae in Mesembria survived a number of reconstructions. They have been destroyed after the capture of the city by the Bulgarian khan Krum in AD 812 and overbuilt by dwellings and domestic buildings. The latest structures attested there are two kilns for melting the marble decoration of the baths arranged in the corners of the central hall.⁸

4. The Early Byzantine churches ⁹

All together three out of the ancient churches in Mesembria have been identified as monuments from the 5th -6th c. The most impressive in that group is the so-called “Old Metropolis” (or St Sophia) situated in the center of the ancient city. The church was preceded by a square atrium enclosed by porticoes and flanked by single rooms to the south and the north. The church itself (25.50 x 20. 20 m) is a three-aisled basilica with a tripartite narthex and a single-apsed sanctuary (Fig. 6). The nave was divided from the aisles by two rows of five massive masonry piers supporting double-storey brick arcades (Fig. 7). The basilica was most probably timber-roofed. A three-stepped synthronon was arranged inside the apse. The apse, semicircular on the inside and three-sided on the outside, was lit by three windows. The construction technique employed was that of alternating bands of bricks and rubble joined with mortar with powdered brick—a technique recognized as typical for Constantinople, the western coast of Asia Minor, the Balkans and Italy.¹⁰ Furthermore, the square nave, the three-sided apse and the entrances opened in the eastern wall find their closest parallels in the basilica of St John of Stoudios in Constantinople (ca. 450). The dating of the “Old Metropolis” varies between the second half of the 5th and the second half of the 6th c. It is considered that by that time it was related to the bishop’s residence not attested yet. A second phase of reconstruction is dated to the beginning of the 9th c.¹¹

The “Eleousa” basilica is situated in the north part of the city at the coast itself. It is a longer than the “Old Metropolis” (28 x 18 m) and its sanctuary was supplied with pastophoria accommodated in triconches (Fig. 8). Two rows of four masonry piers divided the nave from the aisles. The north aisle, however, was carried away by the sea (Fig. 9). Five masonry tombs were accommodated in the narthex (Fig. 10). The building technique is similar to that of the “Old Metropolis” yet much sloppier. Fragments of frescoes and interior marble decoration have been found in the course of the excavations. On the basis of the elaborate three-apsed sanctuary and the deep bema the “Eleousa” basilica is dated to the 6th c.¹²

Another Early Byzantine basilica has been unearthed to the north of the main city gate. It is interesting to note that the basilica overbuilt the temple of Zeus. Similarly to the two basilicas above discussed, it was also a timber-roofed three-asiled basilica (32 x 20.5 m) yet the interior division might have been accomplished by means of columns (Fig. 11). On the basis of analogies with the layout of the “Old Metropolis” and the Constantinopolitan churches of the 5th c. St John of Studius and Virgin Chalkoprateia the construction of the basilica is dated to the late 5th c. In light of the archaeological evidence, the church was damaged in the time of the Avar attack on Mesembria in AD 587 but was reconstructed mostly likely only in the third quarter of the 7th c. In the course of that reconstruction it was reshaped into a cross-domed church the dome of which was supported by rectangular piers. The church functioned until the beginning of the 9th c. when it was destroyed after the capture of Mesembria by khan Krum. The ruins were occupied by a cemetery in the 10th -11th c., while in the 13th c. there appeared a small single-nave church.¹³

5. The churches of the 11th c.

Two churches in Mesembria have been safely dated to the 11th c. One of them, St Stephen (the “New Metropolis”), is one of the most remarkable medieval churches in the coastal city. Its construction in the late 11th c. had been related to the act of promotion of Mesembria as a metropolitan see by that time. Indeed, its layout of a three-aisled basilica, rather untypical for the Middle Byzantine period, can be seen as a reference to the “Old Metropolis” and further, a demonstration of the continuity in the Christian architecture in the city. The “New Metropolis”, however, was much smaller (12 x 9.50 m) than the Early Byzantine basilicas in Mesembria and the nave was separated from the aisles by means of rows of alternating columns and piers. The tripartite sanctuary was articulated in three semicircular apses. The builders employed the construction technique of alternating bands of rubble and bricks (Fig. 12). It is argued that initial patron of the church was the Mother of God. The strongest evidence is provided by the iconography of the earliest layers of the fresco decoration dated to the 13th c. Perhaps by that time the church was largely renovated and its façades were decorated with colored glaze ceramic rossetes. In the 16th c. the nave was elongated and the interior was redecorated with new frescoes as witnessed by the ktetor’s inscription from AD 1559 placed above the main entrance. The wooden iconostasis decorated with fretwork dated also to that period. The last reconstruction of the church took place in the 18th c. when the narthex was added and furniture was complemented with an ambo and an episcopal throne richly decorated with woodcarving.¹⁴

The other church of the 11th c., St John the Baptist, is situated near the northern coast of the peninsula. It is a cross-in-square (14 x 10 m) on piers with barrel-vaulted aisles and three-apsed sanctuary (Fig. 13). The church lacks a narthex. The latter feature as well as the overall appearance of St John the Baptist find parallels in the provincial church architecture in Greece, such as Laconia (southern Peloponessus). The exterior, built of coursed rubble, was enlivened with single tall slender niches on the western, southern and northern facades. Rather unusual is the tall drum that covered the centre of the naos (Fig. 14). Layers from the 14th and the 17th c. have been recognized in the frescoes on the interior.¹⁵

6. The churches from the 13th -14th c.

The five churches representing the style of the Late Byzantine architecture comprised the largest and the most picturesque group of medieval monuments in Mesembria. Since no direct evidence for their patronage and date of construction is available, the only ground for their dating is provided by the arguments based on the construction technique and the style of exterior decoration.

One of the churches dated to the 13th c. is the church of St Theodore (11.00 x 5, 15 m) situated in the northeastern part of the town. It is a single-nave church, barrel-vaulted, with a single-apse sanctuary (Fig. 15). At a later stage it was enlarged to the south. The walls were built of alternating bands of brick and stone reinforced with wooden beams within the brick courses (pseudo-opus mixtum cum ligno). The lateral facades were enlivened by arched niches. Their lunettes were decorated with various brick patterns (checkerboard, zigzag, and herringbone). The western façade was also enlivened by three niches the middle of which was higher and accommodated the door (Fig. 16).¹⁶

There is one more single-nave church in Mesembria, St Paraskeva (14.70 x 6. 60 m) dated to the 13th c. yet it yields some differences in comparison to St Theodore. One of them is the enforcement of the barrel vaulting of the nave by two arches supported by two pairs of pilasters on the lateral walls. In addition, the sanctuary was not separated from the nave and thus, appeared larger in size. The apse was pentagonal on the exterior enlivened by slender niches. The prothesis and diakonikon were articulated only on the interior by means of small round niches in the eastern wall. The most remarkable peculiarities, however, appeared in the narthex. Its central bay was covered by a calotte surmounted by a belfry. Two round niches were shaped to the south and the north of the entrance to the nave (Fig. 17). The construction technique is similar to that of St Theodore yet the facade decoration is more elaborated. A double arcade of eight slender niches ran along the north and south facade, the apse was also flanked by two niches, while three were arranged on the western wall in the way employed in St Theodore church. The lunettes of the arches were also decorated with brick patterns and their tops outlined with ceramic plastic decoration (Fig. 18). ¹⁷

The churches of Pantokrator (16 x 6. 90 m) (Fig. 19) and St John Aleitourgetos (18.50 x 10.25 m) (Fig. 20) are the best preserved medieval churches not only in Mesembria. Both are four-column churches of somewhat elongated shape. The surviving dome of the Pantokrator church was divided into sixteen segments and raised over a drum lit by eight windows. The narthex was surmounted by a belfry (Fig. 21). In contrast to the St Theodore and St Paraskeva, the Pantokrator and St John Aleitourgetos churches were built in opus mixtum (Fig. 22). The lateral facades of the Pantokrator were decorated with a sort of “aqueduct” system with overlapping decorative arcades of slender niches outlined by glazed rosettes and plates (Fig. 23). Ceramic plastic decoration and dentils were also employed in the decoration of the drum (Fig. 24). Yet St John Aleitourgetos had the richest exterior decoration—brick decorative pattering was employed in the heads and the spandrels of the slender niches, checkerboard, herringbone, and zigzag patterns appeared in the lunettes as well as two rows of coble table inspired by Romanesque models (Fig. 25). In the scholarly literature the dating of the Pantokrator and St John Aleitourgetos churches vary between the first half of the 13th c. and the beginning of the 14th c.¹⁸

The same unspecified dating is suggested also for the Holy Archangels church situated in the proximity of the northern coast of the peninsula. It represents the shortened variant of the cross-in-square type with a dome resting on two pairs of pilasters (Fig. 26). Similarly to St Theodore and St Paraskeva, the narthex was surmounted by a belfry. The walls were built in opus mixtum the decorative effect of which was emphasized by arcades of slender niches outlined by triple bands of ceramic plastic decoration and doubled by Lombard arcades above the cornice (Fig. 27).¹⁹
The group of the surviving late medieval churches in Mesembria can be completed with two single-nave churches from the 17th c., St Clement church and the Savior church (Sv. Spas) (Fig. 28). A ktetor’s inscription at the southern entrance of the Savior church indicates that it was built and painted in AD1609 in the time of the metropolitan Kyprianos. On the order of the metropolitan the remains of the Byzantine princess Mataissa Kantakuzene who died in AD 1441 were moved there and thus, her tombstone can be seen in the sanctuary.

7. Stylistic characteristics of the religious architecture in Mesembria

The variety in the architectural types demonstrated by the surviving medieval churches in Mesembria cannot be seen as a local peculiarity but rather a reflection of the development of the perception of the liturgical space. Yet the execution of the architectural elements brings forth the specific appearance of the churches there. For instance, the employment of masonry piers in the interior division of the Early Byzantine basilicas in Mesembria perhaps may be considered a method linked to local workshop practices. As for the Late Byzantine period, one can distinguish two architectural elements which appeared in both single-nave and cross-in-squcare churches and thus, might be viewed as typical for the local architectural design in general—the belfry surmounting the narthex (St Theodore, St Paraskeva, St John Aleitourgetos and the Pantokrator church) and the two round niches flanking the entrance from the narthex to the naos (St Paraskeva, the Pantokrator church, and the Holy Archangels church).

The religious architecture in Mesembria is characterized by employment of brick and stone for massive walls yet in various construction techniques. While the opus mixtum cannot be considered a chronological indicator since it was employed both in the Early Byzantine basilicas and the Late Byzantine churches (the Pantokrator church, the Holy Archangels church, and St John Aleitourgetos), the pseudo-opus mixtum cum ligno appeared a construction technique typical for the medieval churches such as St Theodore and St Paraskeva. Moreover, the use of wooden beams in the brick courses there instead in the stone courses as usually done in the contemporary Constantinopolitan buildings seems to demonstrate the practice of a local workshop.²⁰ In the same time, however, the walls of the Mesembrian churches demonstrate the same integrity of construction one attests as typical for Constantinople.

Perhaps the most distinctive feature of the churches in Mesembria dated to the 13th -14th c. was the external articulation of the buildings the purpose of which was predominantly decorative rather than structural. Thus, the picturesque effect of the construction technique featuring alternating bands of brick and stone was lavishly enriched with arched niches and Lombard arcades that articulate the facades. The lunettes of the niches were decorated with multiple motifs such as checkerboard, zigzag, cross-stitch, “sun-bursts”, herringbone, etc. Ceramic plastic decoration was preferred for friezes dividing the tiers of the facades and outlining the arched niches. All those decorative principles, however, cannot be viewed as particularly characteristic for the religious architecture in Mesembria. As has been already stated, the exterior decoration of the churches in Mesembria is closely related to the Palaeologan monuments in Constantinople and Thessalonica and moreover, a technical analysis supports the presence of Constantinopolitan masons and workshops in the coastal city.²¹ In fact, that peculiar combination of metropolitan and provincial architectural influence is the most illustrative manifestation of the historical faith of Mesembria granted with care and wealth throughout the ages by both the Byzantine emperors and the Bulgarian tsars.