 The region contains many white sand beaches.The region starts at Cottesloe and includes the Scarborough precinct, Trigg Beach, Hillarys Boat Harbour, Mindarie Keys and Perth's northernmost beach at Two Rocks, which contains a marina and was formerly home to the Atlantis Marine Park.While the official Sunset Coast promotion website regards Two Rocks as the boundary, Tourism Western Australia includes the town of Lancelin, 125 km north of Perth, in their definition.