Kärnäkoski fortress was part of the South-Eastern Finland fortification system built by Russians in the 1790's. Purpose of the fortress was to protect the strategic road to St. Petersburg and Russians fleet in Saimaa against Swedish enemies from the west. Building was started in 1790 by French engineer officers and it's a tradional French bastion system. Approximately 1400 Russian soldiers and local peasants were forced to construction work and many of them died in hard work and illnesses.
Kärnäkoski protected the border only 15 years and after Finnish War in 1808-1809 fortress lost its defensive value. Kärnäkoski was disbanded in 1835 by the tsar Nicholas I. After that fortress was disarmed, buildings and remaining equipment were auctioned and the walls and fortifications were left untended. Kärnäkoski never took part to a military action, but in Finland Civil War (1918) several battles were fought nearby.
Today Kärnäkoski fortress is a tourist attraction, although there are no guided tours or other tourist or travel services in the fortress, simply guidance signs. Finnish National Board of Antiquities and Finnish Ministry of the Environment have listed the fortress area as nationally significant cultural historic landmark. NBA has restored Kärnäkoski fortress to its former shape together with other fortresses in south-eastern Finland. Walls were repaired and the fortress area was restored and cleared. Other historical buildings nearby are an old barge harbor, mill and saw built in 1830s and a double-arch stone bridge from 1886. The mill has not been used since 1950s, but was restored by a local village organization in 2002.
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.