Ancient-Mariner:
1991 America's Cup competition off the coast of San Diego, CA.
There was a significantly large no fly and no lower than 1000' zone that obstructed our normal VFR exit and entry routes past Point Loma.
The area was just off the coast, adjacent to and overlapping the ATA for NAS North Island.
We were told that the restrictions were to prevent our rotor wash from disturbing the boats / regatta which were owned and operated by really rich people who had prevailed upon the FAA and Naval authorities to not risk their race being influenced by rotary wing aircraft operations.
Memory is foggy on this, but I seem to recall that the lighter (Jet Ranger) news helicopters also had a restriction that was either the same as ours or maybe a little bit lower. There was a lot of news chopper activity covering the regatta.