Aitoloakarnania is one of the biggest prefectures of Greece. Today it constitutes the Regional Unit of Aitoloakarnania. It is located in the western part of Central Greece and is the largest regional unit (and prefecture) of Greece in terms of area. The capital of the prefecture is Mesologgi and its largest city and economic center is Agrinio. The area has been connected since 2004 with the Peloponnese through the Rio – Antirio Bridge.Also at its northwestern end it is connected by the floating bridge to the island of Lefkada, while through the Preveza – Akti underwater tunnel it is connected to the regional unit of Preveza. The Prefecture of Aitoloakarnania is considered a prefecture of lakes and rivers.