If I remember correctly from articles in the early days of the A380 'arrival on the scene', the ICAO aircraft size category is based on a "box", with cat. F being 80m long, 80m wide and ?? m high. The A380 was sized to just fit inside the "box".
Airports are supposed to be designed and operated using the same criteria.
I tried to Google the subject, but without any success, sorry....
Anybody else ?