Many glacial erratic boulders (often simply called glacial erratics) can be found in the Puget Sound region as far south as the Yelm area where the Puget Lobe of the glacier reached its maximum extent.
[2] According to Nick Zentner of Central Washington University Department of Geological Sciences, "Canadian rocks [are] strewn all over the Puget lowland, stretching from the Olympic Peninsula clear over to the Cascade Range.
"[3] Erratics can be found at altitudes up to about 1,300–1,600 feet (400–490 m) in the Enumclaw area,[4] along with kames, drumlins,[5] and perhaps also the unique Mima mounds.
[3][8] Boulders greater than 3 meters in diameter are "rare" in the Vashon till,[2] but can be found, as seen in the table below.
A legend says that a hero named Sta'kub could throw a giant cedar and hazel branch dragnet over the rock while standing at the beach.