The boys and I were fortunate to have a day out sailing on the boat of our friend, Keith (Vikings fan originally from Minnesota). Another friend, Rob, (Packer fan originally from Wisconsin) joined us. Last year we took Keith's boat all the way around Garden Island. This year we just headed directly to a beach on the eastern side of the island - about a 10km trip each way - for a little picnic and play on the beach.
(See map here.)
Garden Island is occupied by an Australian Naval and submarine base and isn't accesible to the public except by boat. We saw a dolphin alongside the boat and a foot-long lizard that hung around for most of the time we were eating at the beach. Fortunately, we didn't see any of the tiger snakes for which are well-known to populate the island. All-in-all, it was a relaxing summer day with no worries.