This is the Yeni Camii or New Mosque, it's functional rather than nice.

The large (and recent) mosque is an indication of both the wealth of today's Kayseri and of the strong religious feelings of its inhabitants. In addition Yeni Camii shows the reluctance of modern Turkish architects to depart from traditional Ottoman patterns.

In the background (left and right of the mosque): two Classic Ottoman-style entrances of the ‘Kapalı Çarşi’ (Covered Bazar), claimed to be the second largest of Turkey (after the one in Istanbul, of course). Established during the Ottoman period, it was gradually enlarged, and (since these were predominantly wooden constructions) almost as systematically destroyed by fire.
From 1987-1991 on, extensive restorations were carried out, partly in a Classic Ottoman style, in the area adjacent to the high vaulting section built in 1935.

Correspondent: J.M.Criel, Antwerpen
Sources: Website of ‘kayseriden.biz’ & ‘romeartlover.tripod.com’ + Personal visit (2001)