[3] The town of Diakopto is situated on the Gulf of Corinth, near the mouth of the Vouraikos river and at the lower end of the Vouraikos Gorge.

The 750 mm (2 ft 5+1⁄2 in) gauge Diakofto–Kalavryta Railway built in 1885 leads up to the town of Kalavryta passing the Mega Spilaio Monastery at about halfway.

Diakopto is on the old Greek National Road 8 (Athens - Corinth - Patras); the new Greek National Road 8A (also Athens - Corinth - Patras) passes 1 km to the south.

The municipal unit Diakopto is subdivided into the following communities (constituent villages in brackets): In the area there were three ancient Greek cities: Boura, Helike and Keryneia.

The area followed the fate of the rest of Achaea.