A large calligraphy (late-Ottoman, 19th century), combining four ‘vav’-signs (the 27th letter of the modern Arabic alphabet) in its normal and its mirrored form. They refer to the words ‘vakıf’ (pious foundation), ‘veraset’ (legacy), ‘velayet’ (custody) and ‘vasiyet’ (last will/Testament), which are all four related to the concept of the ‘Külliye’.

Külliye, deriving from the Arabic word "kull" (meaning the whole, all) is a term which designates a complex of buildings, centered around a mosque and managed within a single institution, often based on a vakıf (foundation). Additional to the mosque, it can be composed of a medrese (school), a darüşşifa (hospital), kitchens for the poor, bakery, hamam, library, arasta (shops), caravanserai and other buildings for various benevolent services for the community. Often the türbe of the initiator will be present too.
The tradition of külliye is particularly marked in Turkish architecture, particularly Ottoman Empire.

Correspondent: J.M.Criel, Antwerpen.
Sources: Website of ‘bursaulucami.blogspot.be’ & Wikipedia .