Kaal Kadoş Synagogue was built in Alaybey as a place of worship for Jews who settled in Karşıyaka after the spread of the Jewish community out of Kemeraltı. Since this synagogue which was built in Alaybey with the establishment of settlements outside Kemeraltı by the Jews in the twentieth century was not a Sephardic synagogue, it was built with church plan under Italian influence like the Beit Israeli synagogue in Karataş. It has two Tevya; it is located on a platform and has the character of a semi-open space. The interior of the synagogue was considered as a whole, so unlike the usual style no columns were built to divide the space into nine parts. The ceiling is covered with wooden nexus, which are unadorned and flat. The interior of the structure is extremely plain, unadorned and much more lighted than the Sephardic synagogues. The building was built as stone masonry. Ceiling slabs are wooden and the roof of the structure is wooden construction. Floor coverings are tile mosaic. The building is placed in a beautiful courtyard. The courtyard walls of the synagogue are massive stone walls that pass under the eye level like a garden wall and are not constructed as massive and high as in the synagogues in Kemeraltı.