The National Archaeological Museum, in the centre of Sofia, occupies the building of the largest and oldest former Ottoman mosque in the city, originally known as Koca Mahmut Paşa Camii. The construction started in 1451 under grand vizier Veli Mahmud Pasha but due to his death in 1474 the mosque has been completed in 1494. The museum was established as a separate entity in 1893 as the National Museum directed by Czech Václav Dobruský with its headquarters in the former mosque that previously housed the National Library between 1880 and 1893.
Prehistory Hall displays a collection of items dating from between 1,600,000 BC and 1,600 BC. The collection is chronologically displayed and includes various findings from caves around Bulgaria, tools of the earliest humans who inhabited its modern territory, drawings, simple pottery, ritual items and many others.
Treasury displays grave inventory and other treasures from the late Bronze Age to late Antiquity. Two of the most well-known Bulgarian treasures are located here: the Valchitran and Lukovit Treasures. Main Hall hosts a collection of diverse items ranging from ancient Thrace, Greece and Rome to the late Middle Ages.
The medieval Section includes a gallery of medieval books, woodwork, drawings, metal objects and other items characteristic of the era.
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.