It's legal if neither player notices that White castled twice.
Greatest number of castlings: 3

It's legal if neither player notices that White castled twice.
If White castles twice in a forest, and no one is around to call the arbiter, is it illegal?
How on Earth did you do that???
I think there's an option to allow illegal moves somewhere...

How on Earth did you do that???
I think there's an option to allow illegal moves somewhere...
Really???
How on Earth did you do that???
I think there's an option to allow illegal moves somewhere...
Really???
The game editor has a checkbox for enforcing legal moves. Of course, he could have just copied and pasted the PGN, because I'm not sure if there's any checking for legla moves that way.
Greatest number of castlings: 3
Heidenfeld - Kerins, Dublin 1973
Is this legal? (white castling two times?)
http://timkr.home.xs4all.nl/records/