On the civic coat of arms of Castro there is a fortress on the sea. The same name of the village comes from a Latin word that means fortress. We cannot certainly say when the village was founded. The legend says it was founded by Idomedeo, some scholars say the founder was Diomedeo, others say the Pelasgians. Strabone and Erodoto wrote about the temple of Minerva which was in this village. Even if we are not sure about who was the founder of Castro, we can affirm that it was inhabited since the Neolithic age because there are several menhirs and dolmens, as the dolmen ‘Scarra’ and dolmen ‘Rodde’, and we know that those monuments are very old. The scholars think that Castro took part in the war against Taranto in 473 B.C. The Roman domination began in 123 B.C. and then many barbarian populations followed. The Vandals came, the Goths in 545, the Longobards in 741, then Byzantine and Saracens. The Norman domination has been very important for Castro. They fortified the village, made it an important cultural centre and above all, they planned and built its strategic defences along the coasts. The first vassal was Tancredi of Altavilla then the village was ruled by several local families as the Bielottos, de Francos, De Buggiacos. In 1938 the village was taken by the Orsini del Balzo, in 1488 by the Della Posta, in 1534 by the Gattinara, in 1624 by the De Castro, in 1772 by the De Zunica. The last family to rule Castro were the Rossi and in 1806 the feudal system came to end.
Castro has been destroyed twice by the Turks. The first time, in 1537, their chief was Ariadeno Barbarossa but they came again in 1573 and destroyed the whole village. Among the famous people who come from Castro we remember : Deodato (an appreciated writer), Zaccaria Martino, Giacomo Vitelli (Bishop of Bitonto) and Gaetano Favia Vernazza. Paolo di Castro was born in 1360 in a poor family. He worked as a copyist for Ubaldo degli Ubaldi then took his degree in Avignone. He was very popular in many university where he also used to teach. He wrote many law books and died in Padua in 1436.