When Zuko leaves the party and is walking towards his childhood holiday house, there are flashes of his happier memories. One of them is of a man holding a baby with another child next to him playing on the beach - one might assume it would be Ozai holding Azula, with Zuko playing next to them. But it's actually Uncle Iroh holding a baby Zuko, with Lu Ten next to them playing.
Avatar Extras says that the crater the Gaang swim in at the beginning of the episode is based on the Viti volcanic crater in Iceland.
The game that the teens play on the beach isn't actually volleyball; it's game called kuai ball that was created for the show, based on the southeast Asian sport sepak takraw.
Avatar Extras confirms that Chan, one of the boys who hosts the party, is the son of Admiral Chan. In The Awakening (2007), Hakoda and Bato pretend that they are under the command of Admiral Chan.