The Palazzo d'Avalos is the grand fortified palace at the southern end of the centro storico — once the residence of the d'Avalos marchesi, who governed Vasto for centuries. It is now the town's main cultural complex, housing the Museo Archeologico (Roman finds from Histonium, including a fine collection of mosaics), the Pinacoteca (regional paintings), and the Museo del Costume Antico.
The palace itself is the main draw: a Renaissance-on-medieval mash-up with a beautiful garden running down the seaward slope. The view from the garden terrace, looking south to the Punta Penna headland, is one of the iconic images of Vasto.