This is based on a "bridge" anvil, as used in railroad shops in the late 1800's to mid 1900's.
The railroads had them up to 1800 lbs. Mine will likely end up around 800 lbs when complete.
I started this project back when I was younger, in better shape, and a bit over-ambitious.
The body was flame cut from 6 inch plate using a pattern cutter I still own. The legs and base were then welded up using 1 inch plate steel.
Unfortunately the project has been in limbo for about 6 years.
The older I get the less inclined I am to swing a 20 lb. 9 inch right angle grinder for 20 hours or so.
I do hope to complete it some day, but I will likely just sell it at auction.
I can't see every having a practical use for such a huge anvil.