The gorge of Kleissoura is a natural passage-way through the Zygos mountain range (originally known as Arakynthos), northeast of Aitoliko, which connects the area of Messolonghi with that of Agrinio. It is about 3 km long and is classified as a place of historical interest and a landscape of outstanding natural beauty. It may have been formed by river action and could be an old inoperative valley cut by the Acheloos or the Ermitsa rivers. It was also described by D. Vikelas at the end of the 19th century as ‘Kykneia Tempi’, an expression which refers to the work of the Roman poet Ovid ‘Metamorphoses’.
It is a very impressive and imposing landscape, flanked by vertical walls. Its course is not straight and at around the middle a narrowing making a vertical ‘door’ is formed. The sides of the gorge are covered with trees and bushes, while the interior is lined with caves and waterfalls and is home to nesting birds of prey.
According to one view, the remains of an ancient fortification at Fragouleika, at the northern exit of Kleissoura in a position dominating the central part of the gorge, is the site of the Homeric city of Pylene, which participated in the Trojan expedition, and which was later renamed Proschion.
The communication with the area of Agrinio through Kleissoura in later years was difficult and dangerous, as the passage was covered in trees where robbers lurked, safe in their fastnesses. It is even reported that a part of the gorge was called ‘the plain of the graves’ because of the many murders that had taken place there. In the interior of Kleissoura, and specifically at the northern entrance formed between the villages of Fragouleika and Chrysovergi, on a low hill a little south of Fragouleika, there was a tower or tower house. Such buildings were quite common during the Turkish occupation in the 17th and especially in the 18th centuries, usually built by Turkish landowners outside the villages. It is mentioned by the French traveller M. Raoul de Malherbe (1834), together with another tower that existed to the right of the exit of the gorge and was already in ruins at that time. Today only the ruins of one of the towers can be seen.
In the gorge is the monastery of Agia Eleoussa, on the site of the 13th century monastery of the Virgin Eleoussa, known from the writings of the Bishop John Apokaukos.
