Cecilienhof Palace was built from 1914 to 1917. Emperor Wilhelm II ordered the establishment of a fund for constructing this new palace at Potsdam for his oldest son, Crown Prince Wilhelm (William) and his wife, Duchess Cecilie of Mecklenburg-Schwerin on 19 December 1912. Cecilienhof was the last palace built by the House of Hohenzollern that ruled the Kingdom of Prussia and the German Empire until the end of World War I. It is famous for having been the location of the Potsdam Conference in 1945, in which the leaders of the Soviet Union, the United Kingdom and the United States took important decisions affecting the shape of post World War II Europe and Asia. Cecilienhof has been part of the Palaces and Parks of Potsdam and Berlin UNESCO World Heritage Site since 1990.
References:The ancient Argos Theater was built in 320 BC. and is located in Argos, Greece against Larissa Hill. Nearby from this site is Agora, Roman Odeon, and the Baths of Argos. The theater is one of the largest architectural developments in Greece and was renovated in ca 120 AD.
The Hellenistic theater at Argos is cut into the hillside of the Larisa, with 90 steps up a steep incline, forming a narrow rectilinear cavea. Among the largest theaters in Greece, it held about 20,000 spectators and is divided by two landings into three horizontal sections. Staircases further divide the cavea into four cunei, corresponding to the tribes of Argos A high wall was erected to prevent unauthorized access into the theatron and may have helped the acoustics, but it is said the sound quality is still very good today.
Around 120 CE, both theaters were renovated in the Roman style.