In the old times it was necessary to distinguish between the town of Oiartzun (the old Oiasso) and its port, Pasajes, that was called Oyarzo and Oyarzun. As it is stated that there are several kilometers between Oiartzun and the sea, the author bases his research on geology to more or less verify the distance that separated Oiasso from the sea during Roman times. That distance was then possibly some two kilometers and the author therefore deduces that Oiasso was possibly around the same place as the current Oiartzun