The Vouraikos is a river in Achaea, Greece. In ancient times it was called Erasinos. Its source is in the Aroania mountains, near the village of Priolithos. It flows past the towns of Kalavryta and Diakopto, and flows into the Gulf of Corinth near Diakopto. It is 37.5 km (23.3 mi) long.
This is the Vouraikos gorge, which has a length of about 20 km. In the gorge the river passes along dense vegetation and steep cliffs, waterfalls and caves. The Diakofto–Kalavryta Railway passes through the Vouraikos gorge.
According to legend there was a cave on the banks of the river which was dedicated to Hercules. There pilgrims came to read their fate in the Tables of Knowledge, as they were called.