The Malta Alter-Chamber
The Malta Hypogeum is a 6,000 year old subterranean structure in the isle of Malta. The chamber has reportedly mind-altering vibrational effects when activated by a male baritone voice. Malta is in the middle of the Mediterranean sea and is directly between the AM47 Point of Elemental Air and Earth, sharing the same latitude as well.
It would have made a nice stop on the AM47 journey.