That's what I was going to say, Ed Rutsch.

So...

In Secaucus, New Jersey, near Snake Hill (and Little Snake Hill) there
was a large one that is half incorporated into a large truck depot the
other half filled too I imagine.

There is an operating one in North Creek, NY, where Vice President
Theodore Roosevelt read the telegram informing him of the death of
President McKinley in Buffalo, NY and he boarded a special train for
that city after the roundhouse turned it around.

There is a small one in New Hampshire that is part of a park you can
hand spin (without the locomotive of course).

I watched a guy move large stones that way too a small stone pivot
then two small stones. On the Canadian Discovery Channel, who is using
the fulcrum point to build his own "stone henge" single-handed.
Interesting "experimental archaeology".

George Myers