The island chain of Sevrin has seven main islands and dozens of tiny islands, most of them uninhabited.  The Whistling Caves are located along the coast of Karivala, a small, mountainous island located on the northwestern part of the archipelago.

Strong, steady sea winds blow through the caves, producing an eerie sound that varies slightly with the shifting weather patterns.  During the approach of extreme weather, a “storm whistle” can be heard as far away as Stormwatch Island, the most southern of the seven main islands.

Legend has long suggested that Karivala’s cave system was the result of art, not chance. Storyspinners tell of an ancient culture that sculpted the caves to warn inhabitants of storms, or of shifting wind patterns favorable to invading ships.  Most people assume such tales have more to do with entertainment than history, but a recent discovery suggests that the storyspinners stopped short of the truth.

This spring, herring fishermen noticed a new note emerging from one of the caves–a deeper, more haunting sound than any had ever heard from the whistling caves. Two of the younger men–both of whom had explored Karivala’s caves since boyhood–decided to investigate.

They took a row boat into the cave and found that a section of the cavern wall had crumbled.  Existing pieces of the broken wall were surprisingly thin and smooth.  Stranger still were the gouges along the thicker stone next to the break, as if the thin section had somehow been slid aside.

The two men proceeded into this new opening and found a long, straight tunnel. They saw no other breaks, but at several places, just above the water line, they saw similar gouging on the stone. These “unopened portals” seemed to be placed at regular intervals, giving the impression of a gigantic stone flute.

Though this discovery is a matter of mystery and wonder to the inhabitants of Sevrin, any dwarf would understand the implication immediately.  The Karivala caves are evidence of a long-gone dwarven culture, and the tunnel is exactly what it looks like:  A wind instrument carved into the island’s stone.  A group of stoneshifters could move these portals at will, changing the pitch and volume of the sounds coming from the caves to send messages to the rest of the islands.

Any dwarf who hears of the herring fishermen’s discovery is likely to be very concerned, particularly those dwarves who are secretly laboring beneath the streets of Sevrin. They don’t want to draw human attention to the very civilization they are working to undercover and reclaim.