There are mosques all over the medina; interiors are off-limits to non-Muslims. The finest include Kasbah Mosque, which dates from 1235 and was once within the Hafsid citadel, which no longer stands. The minaret's lozenge design pays tribute to Moroccan style, purposefully showing the Hafsid's links with the Almohad strand of Islam. It was hugely influential, serving as a model for the Zaytouna Mosque minaret. The call to prayer is quietly signalled by a white flag.