Daugavpils Fortress, also known as Dinaburg Fortress is the only early 19th century military fortification of its kind in Northern Europe that has been preserved without significant alterations. For a long time it was a defense base of the western frontier of the Russian Empire. Planning of the fortress began in 1772 by decree of Tsar Alexander I of Russia, shortly after the First Partition of Poland when Latvia ceded to Russia and construction began during Napoleon"s attack of the Russian Empire in 1810. In 1812, the fortress was attacked by the French Army of 24,000 men. The fortress was still under construction and was defended by 3300 men and 200 cannons.
Construction of the fortress, despite lengthy delays, serious floodings and slow construction work, was completed in 1878. Latvian independence was officially recognised by Soviet Russia in 1920 and between 1920 and 1940 the fortress became home of the Latvian army. During World War II, the hostage camp Stalag 340 was set up in the fortress.
Today fortress is the site of the Daugavpils Mark Rothko Art centre.
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.