Photo is courtesy of “wolftracker” who published it on Flickr. Wolftracker wrote to me:
This is the floor design throughout most of Qait Bey Citadel in Alexandria, Egypt. I took the picture because I find the prevalence of the Star of David in Islamic architecture to be very interesting. The Citadel was built in the late 1400s on the remains of the Lighthouse of Alexandria during the Mamluk period. The mosque it contains is believed to be among the oldest in Alex.