borj el kebir, borj el ghazi mustapha an ancient castle in houmt el souk, tunisia on the island of djerba

tunisia djerba castle houmt souk africa kebir borj travel city landscape construction wall white sea architecture old stone beautiful tourism mediterranean fortress archaeological traditional ancient outdoor tower monument outdoors landmark history town fort museum heritage historical historic mahdia destination ghazi famous build arab mustapha island djerba largest preserved local one visited sites island