Google Maps has this as the Erkekler Hamam, the men's bath, it is situated across the road from the elevated park that is to the south of the Sokullu mosque. I suppose it may have had a different name when founded, in, according to my source, the 16th century. As it is hard to keep me out when I come across an interesting building in a restoration phase I went in and to my surprise found no-one to stop me. These pictures are the result.