My wife is 5' 6" and the spool was from Germany. The reason it was so big was that it held 500' of 6" RF Waveguide for a TV tower.
Waveguide can't be kinked so the inner drum is roughly 9' in diameter and the spool (from flange to flange) was 8' wide.
I must have looked at that thing 100 times over the years and only until a year ago May I had the bright idea I could make a play house out of it.
Things just sort of got out of hand since then!