The best place to find, Castoroidies, or Giant Beavers on Ragnarok, is a place called Beavertopia, which is located near Viking Bay. The beavers and their dams are located in two ponds connected by a river in the Great Plateaus region. Beavers dams can also be found in the Redwoods, and south of the Green Obelisk. Beaver dams come in three styles on the Ragnarok map, so be sure to check them all out to get all that free cementing paste and wood.
Beaver Dam Location
Beavertopia 24.5 42.5
Pond near Beavertopia 28.3 41.9
Redwoods 39.7 78.5
Near Green Obelisk 62.7 35.8
Some beaver dams look different on Ragnarok, some are huge doughnut-like structures,
some actually look like a beaver dam!
You can also find the old-school Castoroidies dams too.