souvenir: noun, \ˈsü-və-ˌnir, ˌsü-və-ˈ\
a token of memory, often given to those as gifts who did not make the trip.
As you make your way around the perimeter road to the four different listening stations, acquire a free postcard at the kiosk to keep or to send to a friend or loved one. Collect all 4. map of station locales