The sanctuary of Messon in Lesbos was one of the most important Panhellenic sanctuaries of the people of Lesbos in ancient times, while today it is one of the most remarkable archaeological sites of the island. It is located in the “Koukala” or “Kokkala” location in the area of Mesa (or “Messon”, according to the ancient Aeolian form of the word) in the centre (middle) of the island, from where the wider area took its name. It is 1.5 km. from the cove of the Gulf of Kalloni and 35 km. from Mytilene. Nowadays, the area of Mesa belongs to the rural district of Agia Paraskevi. In ancient times, the homonymous sanctuary of Messon (‘in the middle‘, which translates in ancient Greek as ‘Messon‘, by which it took its name according to the epigraphic evidence: IG XII, Suppl. 136, fr. a.5, b.32, b.45 and IG XII, Suppl. 139, C.70, C.79), was located on the northern border of the territory of the ancient city of Pyrrha and was 5 km. in a straight line from it and 7.5 km. from ancient Arisvi. Spatially, it was located within the boundaries of ancient Pyrrha but in essence, it was an independent place of common worship, where the people of Lesbos celebrated their common Aeolian origin and the first settlers.
The sanctuary of Messon was a centre of worship for the people of Lesbos, dating back to the Mycenaean era, while until the 2nd c. AD, it was the official seat of the Community of the People of Lesbos. References to the sanctuary are made both by Sappho (fr. 17) as well as by Alcaeus (fr. 129.2-9). In one of his stasiotic poems, the sanctuary of Messon is referred to as “this great and conspicuous sanctuary” (fr. 129.2-3), that is, a large and common (for all the people of Lesbos) sanctuary, standing out from afar. From the same poet we are informed that the temple was dedicated to the “immortal Gods” (fr. 129.4), that is, to the triad of Lesbos: the pleading Zeus, “God of suppliants” (fr. 129.5), Hera, “Aeolian glorious goddess, mother of all” (fr. 129.6-7), and Dionysus, “Kemelios, the eater of raw flesh” (fr. 129.8-9). Initially, worship in the sacred temple of Messon was open-air and altar-like, “and in it they put altars of the blessed immortals” (Alcaeus, fr. 129.3-4).
From the Archaic cult building of the sanctuary (rectangular floor plan with E-W directions), fragmentary architectural remains are preserved and more specifically, a small part of the foundation and the crepidoma. In the Late Classical period, a new Ionic, pseudodipteral temple consisting of eight colonnades was built, with 8 x 14 (8 on the narrow sides and 14 on the long sides), amphidistyle (with two columns) in antis, with a pronaos, a cella and an opisthodomos and maximum surviving overall dimensions: 23.78 x 41.55 m., which incorporated the older temple in its foundation. The elongated rectangular floor plan of the main temple was 9.80 m. wide and 27.60 m. long. The drums of the Ionic columns of the wing had 24 banded volutes. The entablature consisted of a three-lined epistyle and an unadorned frieze, topped with decorative strips. Next came the horizontal cornice and its supports, the pediment with a relief decoration of a sprout on the long sides, and the cornice raking with a decoration of palmettes and lotus blossoms on the narrow sides. The temple had no gable sculptures, while the roof was made of clay. Corinthian-style covering tiles (imbrices) and rain tiles decorated with palmettes and called antefixes were used. Mostly off-white volcanic stone was used in the construction of the temple. However, the walls of the cella, the unadorned wing frieze and the unadorned tympanum of the pediments were made of red stone, while the lion-headed aqueducts and the central acroteria with palmettes were probably made of white marble.
In the temple of Messon we find for the first time the application of the pseudo-dipteral floor plan in a temple of Ionic style. According to Vitruvius (III.3.1-10), the invention of the pseudo-dipteral temple is attributed to Hermogenes. Nevertheless, there is no unanimity in the research, as far as the question is concerned: the activity of Hermogenes is chronologically placed in the last quarter of the 2nd to the first quarter of the 1st c. BC, whereas the temple of Messon dates back to the Late Classical period (330-300 BC), while examples of pseudo-dipteral Doric temples or similar variations (pseudo-dipteral only on the long sides) are found as early as Archaic times in Sicily (Selinunte, Akragas) and Corfu (Temple of Artemis). Unfortunately, the architect of the temple of Messon is not known to us. However, taking into account the historical context, most scholars attribute the construction of the temple to an architect who was active at the end of the 4th c. BC and was a contemporary of Pythius of Priene.
In the 3rd c. AD, the temple was destroyed by an earthquake, while in later times (4th c. AD), the site acquired a workshop character, as can be seen from the furnaces found around the perimeter and in contact with the temple, on its western and northern sides. The architectural elements of the temple are literally fragmented and scattered in the wider area. Architectural fragments were reused as building material, while many more were lime-washed in the adjacent kilns. In the 5th or 6th c. AD, a three-aisled early Christian cemetery basilica was built on the site of the temple (on its foundations). In the post-Byzantine period, the basilica was destroyed and its place was taken by a smaller one-room church (temple) dedicated to Archangel Michael.
The first reference to the temple of Messon was made in 1856 by the French traveller Jean-Marie Ernest Boutan (1827-1880), while the first excavations at the site were carried out by the German architect and archaeologist Robert Johann Koldewey (1855-1925) in December of 1885 and January of 1886, who uncovered almost half of the temple and then published the findings of his study in 1890. In later years, excavation research at the site continued: between 1966-1968, by the 7th Archaeological District of Mytilene, led by archaeologist Vasilios Ch. Petrakos, and later, between 1987 – 1988, 1995 – 1996 and especially between 2002 – 2004, from the 20th Ephorate of Prehistoric and Classical Antiquities, at which time the project was included in the 3rd Community Support Framework (CSF) 2000 – 2006. Apart from the purely excavating work, which fully revealed the monument in its maximum surviving dimensions, a series of systematic works were carried out in order to shape and enhance the archaeological site as a whole. At the same time, a semi-open-air exhibition area was created, which houses the few remains of the fragmentary architectural parts of the temple, accompanied by the relevant design and pictorial representations of its facade, thus giving the visitor the opportunity to better understand the monument in its entirety.