After the Asopos Station we come across a 350m long tunnel, which comes out at Asopos Bridge. It is above the Dounos gorge, which descends from Pavliani, Papadia Bridge which is 352m long and then further on is the big Bralou tunnel. The area during the occupation gained the interest of the rebels with the blasting of bridges, other than the Gorgopotamos Bridge, and the need to protect it over the last few years with a military guard. Military outposts still exist today. The Asopos Gorge is also known as the Efialtis passage, since the area of Efialtis led the Persians behind the Spartans', who had been lined up in Thermopylae.
It is of particular archaeological interest, because the ancient Iraklia, Tracheina, Iron Gate and Kouvelos of Pavliani, where there is also a Byzantine Castle. Indeed, it is said that in 1997, when the landslides happened in the Asopos area and operation of the line was interrupted for a month, four tombs were found at the site of the landslide, of which two were intact, but had been raided.
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