The tower of Martinsicuro or tower of Charles V, is located on the Adriatic coast, in the province of Teramo, near the mouth of the Tronto river, in the municipality of Martinsicuro.
It differs considerably from the other coastal towers of Abruzzo while it has similarities with those of Lazio, Marche and Campania.
The tower and the adjacent customs house, recently restored, house the Environmental Education Center Blue School of Legambiente and in 2009 became home to the Archaeological Museum Antiquarium of Castrum Truentinum.
