Isonzo: Italian offensive on Carso from Kostanjevica to sea aided by 60 British guns and Royal Navy monitors begins with 6-hour barrage from 0600 hours, attack at 1600 hours with 130 aircraft in close support. Four hills stormed. Austrian attacks beaten off on May 24.
Britain: 6 Navy airships fly against London but nearest 40 miles away; (1 fatal casualty to 60 scattered bombs during night May 23/24). 76 defence sorties only sight 1 Zeppelin, and 1 plane of Royal Navy Air Service failed to return.
Italian Front: D’Annunzio flies in aircraft over Carso, wins third Silver Medal, promoted Major on September 29.
Palestine: ALH (Australian mounted infantry) and Camel Corps destroy 13 miles of (and 6 bridges along) Turk Beersheba-Auja railway.