Hypostyle order: The anatomy of a wooden structural system

In architectural terminology, the term “hypostyle” describes a layout in which the ceiling or upper covering of a place of worship is supported by numerous posts or columns. In Anatolia’s wooden mosques, this system takes shape as a hybrid structure; the outer walls are built with rubble or cut stone, while inside, a flat wooden ceiling is carried by timber posts and a network of primary and secondary beams that connect them.
A closer look at the construction techniques reveals a nave with rows of supporting posts and wooden tie beams set above the capitals. Two main solutions appear side by side in these capitals: “muqarnas” (form of Islamic decorative art) capitals, reflecting the intricacy of wood carving, and spolia (recycled elements), stone or marble capitals reused from the Ancient Roman or Byzantine periods. In the minbar and door wings, the “kündekâri” (interlocking wood technique) stands out, with wooden pieces interlocked without nails to form intricate geometric compositions.
Historical context: from the Seljuks to the Beyliks (principalities)

The five core UNESCO-protected mosques were built between 1272 and 1367. This period coincided with political transformation in the Anatolian Seljuk State, as local principalities grew stronger and more established. The wooden-columned mosque type is considered a unique synthesis in Anatolia, combining a structural tradition rooted in Central Asia with hypostyle forms found across early Islamic geographies and within the Central Asian belt. These structures are regarded as some of the best-preserved examples in medieval Anatolia of the fundamental concept of wooden posts supporting a flat ceiling.
UNESCO serial heritage: Five core structures
The structural and historical characteristics of the five sites, located across different regions of Türkiye and inscribed on the UNESCO World Heritage List as a serial property in 2023, are as follows:
Afyonkarahisar Grand Mosque (1272-1277)

The structure, following a Kufa-type plan, is one of the earliest prototypes of the wooden-columned type in Inner Western Anatolia. Its exterior, built of stone and brick, encloses an interior with a ceiling supported by 40 wooden columns that form nine naves perpendicular to the qibla. These columns, crowned with muqarnas capitals, together with the painted ornamentation on the wooden ceiling, define the building’s architectural identity.
Eskişehir Sivrihisar Grand Mosque (1274-1275)

One of the largest structures on the UNESCO list by scale, the Sivrihisar Grand Mosque contains 63 wooden columns in its main prayer hall. Some of these columns feature reused capitals and bases. With its dense wooden structural system, the building showcases the craftsmanship of its period across a remarkably expansive interior.
Ankara Ahi Şerefeddin (Arslanhane) Mosque (1289-1290)

Located in Ankara’s Altındağ district, the structure follows a basilica plan. Its wooden ceiling is supported by 24 timber columns, some of which feature reused Roman-period Corinthian and Doric capitals. Profiled wooden cushions above the columns and tie beams, running perpendicular to the mihrab, define the structural system. The minbar, crafted using the kündekâri technique, is among the notable woodworks of its time.
Konya Beyşehir Eşrefoğlu Mosque (1296-1299)

With its slightly irregular rectangular plan oriented toward the northeast, the Eşrefoğlu Mosque is organized around 41 wooden columns, which divide the interior into seven aisles across six rows of supports. It stands out for its mosaic-tiled mihrab and muqarnas-carved wooden capitals. At the center of the building, an open feature known as a “karlık” (snow pit) serves as a functional architectural element, regulating the interior climate and maintaining the wood’s moisture balance.
Mahmut Bey Mosque in Kastamonu Village (1366)

The structure, laid out on a rectangular plan and featuring a covered portico on the north that serves as the final congregation area, is also known locally as the “Nail-less Mosque” because its roof system is built using the traditional stacking technique. The exterior walls are constructed of rubble stone, while both the prayer hall ceiling and the final congregation area are supported by wooden columns. The building offers a finely detailed example of the era’s timber joinery and stacking techniques.
Conservation and restoration: The dynamics of the timber structure

Timber hypostyle mosques are among Türkiye’s 22 properties on the UNESCO World Heritage List. To explore other cultural and natural sites on the list, you can read our article on places from Türkiye inscribed on the UNESCO World Heritage List. Preserving the structural integrity of these timber hypostyle mosques, recognized as world heritage, requires constant monitoring. According to ICOMOS and UNESCO evaluations, the main challenges to their conservation include moisture and drainage issues, biological deterioration that can cause cracking or fiber separation in the wood, and the risk of fire. Originally, these structures mostly had flat earthen roofs; over time, due to maintenance and insulation problems, they were converted to pitched roofs using tile, copper, or lead. The impact of such interventions on the load balance of the timber structural system is one of the most sensitive aspects of present-day restoration and conservation plans, namely site management plans.
To take a closer look at the architectural details of these historic timber hypostyle mosques and witness Anatolia’s medieval heritage, you can create your own travel itinerary to the relevant cities. By considering flights to Kütahya, Ankara, Konya, and Kastamonu, you can begin your journey to discover these centuries-old structures.
