Gastouni, the administrative centre of the municipality of Peneia has a long and interesting history. It was a booming town during the Frankish rule and then the civic centre during the Ottoman rule, it also played a vital role during the War of Liberation in 1821. The town hall is housed in the historic Sissini residence and is the main landmark together with the Byzantine church of the Holy Virgin and the monastery of Agia Eleoussa. Other destinations worth visiting when in Gastouni are Arkoudi beach, Thines forest as well as Glyfa beach

The municipality of Peneios was established after the merging of the pre-existing municipalities of Vartholomio, Gastouni and Tragano.  Gastouni, which together with Vartholomio played a major role in the War of Liberation of 1821, is the administrative centre. Gastouni, which was linked to the silk road, has been an important civic centre for centuries. Its role extends from the Byzantine era, the Frankish  rule, the Ottoman rule and finally became a destination for Greek refugees that fled Turkey after 1922.
The municipality remains one of the most prominent centres in the prefecture as regards agriculture and stockbreeding while due to the beautiful surroundings and the long coastline it also attracts many tourists. All three main towns that comprise the municipality, that is Gastouni, Vartholomio and Tragano have a lot to offer.
As for the best destinations, there are plenty. Arkoudi, which is by the sea, is cosmopolitan and reminds visitors of a Greek island and not the mainland. Other beaches worth visiting are Thines near Vartholomio and Glyfa. As for tourist attractions, nobody should miss the monasteries of Agia Eleoussa near Glyfa and Agios Nikolaos at Kavassila. The seaside settlement of Bouka is a lively resort  in summer as the locals daily visit it. Also the beach of Palaiochori is a popular destination as the beach is next to a lovely forest. In recent years the municipality of Peneios has been holding the local Cultural and Artistic Festival hosted at the stone theatre of Kavassila.

Population: 21,255 (2011 census)
Municipal districts: 7
Capital: Gastouni

Sights of municipal district of Gastouni
• Church of the Holy Virgin
• Kourvissian Cutlural Centre
• Sissini residencs (town hall)
• Monastery of Agios Nikolaos at Kavassila
• Church of Agios Nikolaos
• Eleftherias (liberty) square
• Municipal library of Gastouni Sights of municipal district of Vartholomio • Monastery of Agia Eleoussa
• Folklore museum of Vartholomio
• Central market
• Arkoudi settlement Sights of municipal district of Tragano
• Folklore museum of Agia Mavra (under construction)
• Demarcheio (town hall) square