Collegiata di San Secondo (13th century) is a medieval church in old centre of Asti next to the Palazzo Civico. It is dedicated to the city's patron saint, Secundus of Asti. The crypt is from the 6th century. The façade has three notable Gothic portals, while the interior houses a polyptych by Gandolfino d'Asti and other works.
Duino Castle was built by the Wallsee family in 1389 on the cliffs overlooking the Gulf of Trieste. It replaced an older castle from the 11th century. Over time, the Wallsee family disappeared and the castle, after having been used as a prison, became the residence of the Luogar and Hofer.
At the end of the 19th century it became the property of Prince Alexander von Thurn und Taxis from the Czech branch of the House of Thurn and Taxis. It remains with the family to this day with his great-grandson Prince Carlo Alessandro della Torre e Tasso, Duke of Castel Duino the current owner. The castle has been opened to the public as a museum and park.