The Great Shoals is a region of icy waters and shifting sandbars above the north of the continent of Amber. This icy watery region caps the globe but does not create an ice cap. Instead wintry weather causes glacial sized iceberg that wedge onto the sandy ground.
The shifting sands and frequently shifting water depth makes shipping nearly impossible. No water based shadow paths leave the realm or arrive in the realm this way.
In general the depth of the water is in the 100 to 4000 foot range, although frequent sandbars breech the surface. Shipping is extremely dangerous. Never the less the Navy maintains a harbor at Port Blue, though it is mostly a military base it is also a popular tourist destination for peoples of icy realms.
This deep water harbor at the north of the continental mass of Amber maintains a small but fierce military presence of peoples from frozen and cold water peoples. There is some commercial shipping and some industry mostly involved in fishing and Great Shoals pearl diving. Nearby are a few mining operations and a some timber companies dealing in exotic woods.
The Great Shoals are a rich region for pearl bearing mollusks of a great many types. Pearl Hunters endure great hardships to harvest pearls in the arctic conditions. The Amber Pearl Oysters have a mechanism to eject pearls so that killing the mollusk is not required.
Ice Pearls, a clear type of pearl, are found in these waters and are highly prized.