Zarax, located on a hill above the current village of Geraka (or Limani Gerakos), has remains of archaic / classical wall, possibly reused in the Middle Ages, and several (ruinous) churches. The temple of Apollo, mentioned by Pausanias, has not yet been located; of the city walls of Zarax, especially the north side is in relatively good condition. An acropolis is fortified separately. The site was (July 2009) poorly accessible and difficult to find.
Photos above from left to right. the bay of Zarax (2 x), with the entrance from the west, below the western gate, ruined church, north wall. Both maps (click to enlarge) are taken from Papachatzis.