Castel del Monte is one of the most mysterious places in Italy and, absolutely, a Puglia place worth visiting. In 1996, UNESCO included Castel del Monte on their World Heritage list for its outstanding universal value as much for its architectural beauty and for the mystery that still surrounds it. The castle is situated on the peak of an isolated hill in Andria, overlooking the Murgia Valley on one side, and with a sweeping view of the Adriatic Sea on the other. It is characterized by an unusual octagon shape with octagonal towers at each corner. Puglia's most famous sight is the trulli, unique houses with conical roofs found in the area around Alberobello. Trulli dot the countryside of central Puglia but the highest concentration of trulli is in the town of Alberobello itself. Its trulli zone has been declared a UNESCO World Heritage Site. Ostuni, the White City is a favorite destination for foreigners. Although Puglia has several towns whose buildings have whitewashed walls, Ostuni is one of the largest and most visible. Sitting atop a hill, Ostuni's white buildings make it stand out against the blue sky creating a beautiful image. You can wander through the old alleys of its historic center, a pedestrian zone, inside its ancient walls, and enjoy the views from the hilltop.