Bay Lake
What are those stone structures at the end of Lake Del Valle in the East Bay CA?
They seem pretty mysterious/secret government type stuff. I'm really curious to know the history of these structures.
I found a long series of giant concrete walls 50' high 85' long 10 foot thick, they turned out to be blast walls designed to dissipate nuclear shock waves, they went on for miles, only accessible by extreme 4wheelers. In Minnesota!
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