[1] The western end of the National Road is in the small town Thermo, in Aetolia-Acarnania.

It turns north at Agrinio, and continues through the sparsely populated mountains of northeastern Aetolia-Acarnania.

The highway crosses the Kremasta reservoir by the Episkopi bridge.

East of Karpenisi, it passes through a tunnel under the Tymfristos mountain and enters the Spercheios valley.

It follows the river Spercheios downstream, through Makrakomi and Leianokladi, and ends in Lamia.