Oh my gosh, you must mean the Long Wall that was built by Perikles (Pericles) which extended from the city of Athens to the port city of Piraeus. The Long Wall was an aggressive project and was clearly a defensive measure against the threatening military might of Sparta built just before 431 BCE. After the Peloponnesian War (404 BCE), the Spartans demolished part of the Long Wall so that they could have access to Athens.
Sorry, the Long Wall was not called a PSALTERION.