Arene

At night a messenger comes to warn Neleus in Pylos and he sets off with an army the same night.

Ilias Book 11 line 736-737 Barry B Powell
Ilias Book 11 line 746-748 Barry B Powell

The mouth of the river near Arene

Considering the previous findings we can roughly chart the area of Neleus' and later Nestor's Pylos. It covers only a small part of modern Messinia and a small part of modern Elis. Most of it is called Trifilia. It stretches from the river Alpheios to the North and East to the steep mountains that form its border to the South.

Let's continue the story of Thryoëssa:

There is a certain river, the Minyeïos, that goes into the sea near Arene, where the horsemen of the Pylians waited until the bright dawn.

The Epeians set up their camp around this city, eager to raze it to the ground.

So, we have to look for a city or area called Arene where there's a river that flows into the sea. That's not so hard, because there's a place called Arini with a river closeby. Arini itself lies a bit more inland beyond the modern town of Zacharo, the river could be the small one South of the Alpheios just below Zacharo as shown on the map on the right. The horsemen must have used the beach to get there and waited till dawn for those on foot.