what's the world's biggest circuit/motherboard?

[Andy Holt]

I think the largest PCB I've seen is that for the Whitechapel workstation -
tho' the boards for the Gould 9000 and Honywell L66 come fairly close.

I suppose some old mainframes might have their entire "engineers panel" on
one PCB.

I suspect that very few boards were made that are wider than a standard 19"
rack.

Andy