Rottnest Island is located just a short ferry from Freemantle or Perth. I’d advise going for a day trip as everything is more expensive on this tiny island. There are no private vehicles allowed on the island, the main method of transport is bicycle, and you can hire them for the day when you reach the island for about $15-20, just follow the signs from the ferry dock.
We decided to cycle the track which circles the perimeter of the island, which only works out as about a 22 kilometre loop. There are 63 beaches around the coast of the island, each one equally as stunning with turquoise water and white sandy beaches. There are 14 shipwrecks along the coast also, which you can spot from some of the various beaches. If you’re getting bored of the beaches, head slightly inland where there are several huge crystal clear lakes.
Less on the cultural/natural side of things but still worth noting is that there is a subway on the island that does pizza, one of the few in the world which has introduced this so far. If you feel like being very English head into the village and try it!