According to researchers, the Castle of Kyparissia was built by Frankish people on the site of a previous Byzantine fortress.
The Byzantines had built four bulwarks at the four corners of the castle, but only one is preserved today, which is named Ioustinianos, after the great Byzantine emperor. The Franks attacked the Castle in the 13th century and kept it under their control for two centuries. As it is built on a hill overlooking the whole town and bay of Kyparissia, this Castle was a watch outpost for enemies and pirates.
In 1460, the Castle of Kyparissia was conquered by the Turks, until the 1820s, when the Greek War of Independence set the town free. However, due to the battles that have occurred, the Castle has been greatly damaged. Most of the bulwarks, the walls, the cisterns, and the storehouses have been destroyed either by attacks or from the gradual decay.
In 1970, there was an effort by the Greek government to restore the Castle. A small open-air theatre was built, which now hosts occasionally a number of cultural events, such as musical concerts, poetry nights and ancient tragedies. In summer, there is a refreshment stand where you can enjoy a cool drink while you see the great view of the surrounding area.
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.