When you get to the cache you'll see how the Millstone Trail got
it's name. Apparently millstones were carved out of local rock at
this site, then hauled off to the mill.
The cache itself is hidden under a nearly completed millstone
and about 20 feet away you'll see another in a much earlier stage
of manufacture. If you look closely at that one, you can see the
drill holes and chisel marks in it, even though it hasn't yet been
formed into the telltale round shape.
There is a third completed millstone about 50 yards to the east
on the other side of the trail.
I'm not sure when these millstones date from and I have no idea
why they were left at the site, even though some were close to
completion. Perhaps the mill shut down. Perhaps the the person
carving them passed away. The reason is lost to time.