Since the V century Otranto had been protected by a surrounding wall with 100  towers.

 Such defences were reinforced by the Byzantine, under Narsete, at the end of the Gothic war  in 553 AD. The works  went on up to the Norman conquest, in 1070.

Some fragments of the  ancient walls  built  with  local materials,  remained in  various parts  of the defensive  structure.

At the end  of the XI century, under the Norman domination, as the construction of the Cathedral had been started,  the surrounding walls  and the adjoined  Citadel were widened.

Other works were carried out by Frederick II during  the following Swabian age, to strengthen the defences  considered inadequate after having suffered more than a Saracen attack, and from Angevin and Aragonese.

sacked the town.

They slaughtered eight hundred men who didn't want to abjure their Christian faith.

They established  their headquarters in the Castle.