Oldest shell horn found in a cave in 1931 plays its songs as clear as the sea

The horn was found in Marsoulas cave that isn't located near an ocean, so prehistoric people either moved around a lot or used trading networks to get it.

from http://www.firstpost.com/tech/science/oldest-shell-horn-found-in-a-cave-in-1931-plays-its-songs-as-clear-as-the-sea-9292461.html