A small mihrab inside the Hacı Bayram Mausoleum, flanked by two heavy stone vases filled with tespihs (= prayer beads).

Although not mosques (nor mescit/small mosque), some important ‘türbe’ – mostly those who cause pilgrimages - have such a prayer niche, indicating the direction of Mecca. Facing the Kaäba is an obligation, only during formal prayer (‘salat’, or as Turks say: ‘namaz’); it is not during ‘dua’ (personal prayer or supplication).
Nevertheless, some pilgrims may prefer the formal position for praying, knowing that anyway most Islamic authorities judge ‘praying to a saint for intersession’ (called ‘Tawassul’) permissible, only if practised as collective supplication (named ‘dhikr’). Which means: not as a personal deed.

Correspondent: J.M.Criel, Antwerpen.
Source: Wikipedia.