The legend tells that the first population estabilished in Vasto came from Dalmazia.  It was called "Histon" o by Diomede, a greek, remembering the Histone mountain, in Corfù. During the centuries the city grows, expecially under the Roman empire.

The barbaric invasions seems to be fatal for Vasto, loosing all the ancient privileges and the name too. A french conqueror, Aymone, built on the ruins of Histon a new village, called Guast d'Aymone. After the Angioin period, whose influences on the local speak are still presents, the control of the city was taken by the D'Avalos family. With this spanish family for Vasto started a new era, so beautyfull that the city was called "Athens of Abruzzo". The marvellous "Palazzo D'Avalos", the residence of the spanish family, rapresented the center of the cultural and political life of Vasto for many years. In the 500th the Turkish destroyed it, but it was rebuilt  and now, inside it, there 're a Museum of Archeology and a Pinacotheca.

The city preserves many other memories of its past.

Castello Caldoresco Built in the first part of the 15th century on the preexistent palace of Giacomo Caldora, the lord of Vasto. Four buildings crowning a brickyard.  Nowadays the Castel host both a residential complex and a commercial space.