You didn't plant any potato there, did you?

Just sod but the lake has never been higher.

My shoreline has done the same thing several times when there is not much snow cover and there is extreme cold. The ice on the lake expands to the point where it pushes up the bank. Makes it hard to mow now since I have never done anything about fixing it for fear that it will just happen again anyway..

If that is a mole, then I would hate to see the size of the crawlers and worms he is feeding on. Changes one's thoughts on digging a few for bait.

Bryce

I would send a pic to a universities' geology dept

I get them along our lake every spring. I'd say a frost heave too.
If not and it is from the movie, Tremors. You'd better get out your big guns, rocket launchers, bazookas, 50 cal, etc.

I can't believe nobody has figured this out .
Crawdads did it

You've read the story about Jack and the Beanstalk, right?

Yep. Frost heaving is one of the primary construction/engineering challenges in Alaska. A ridge like you've got is caused by a seam of soil that hold more water than the surrounding ground, so when it freezes it expands much more. Underground seeps, hydraulic soils and capillary action all come into play. When it thaws the sod will most likely stay humped up but the ice will disappear, leaving a void. Jump on it in the spring and you'll probably go right through .
Here's another article about a road mitigation project if you're interested https://www.geosynthetica.com/frost-heave-dalton-highway-tencate/

You better get a .50 cal. ready for those big worms that make those tunnels. Watch for the sink holes and dont make alot of noise walking in that area. Best to go bare foot as good advice.

Giant vole came through one night. Glad it didn’t eat your tree’s roots.

I'd Say!

Our gravel roads do that too

That's a mountain of a mole hill