River Arachthos passes through Arta and a part of Ioannina.

Arachthos is the 8th river in length in Greece and the biggest in Epirus, with 110klm length. Its characteristic is the arched bridges that connect its banks, like the renown Bridge of Arta and the beautiful Bridge of Plaka. In Arachthos and especially in the location of Pournari a dam has been constructed (being the second biggest in Greece). This lead to the creation of the artificial lake of Pournari which is now an important wetland. The river opens into the gulf of Amvrakikos, thus creating a delta which is considered to be one of the best retained ecosystems in Greece, as it is either the home or the layover for many different species of birds.

Arachthos is also a favorite spot for rafting, with routes suitable for experts and amateurs.