Yes, they are cribbed with rocks which keeps the ice from moving them. They have a floor, then a possible two more partitions or floors with rocks in between depending on the depth. Some have just stringers between the cribs and then some will be totally enclosed between cribs. Most wharfs are hand-built so thus that kind of design.
That would be awesome for you to visit. Lots of laid-back friendly people and wholesome lifestyle in NL.
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