Despite its ideal location, Perth can't be taken seriously as a city for surfers due to a shallow offshore seafloor, known as the Five Fathom Bank (approx 10m), which absorbs most of the swell. Surf is usually mushy and summers are mainly flat, maxing out at 4ft. It's ironic that the entry point for wave-rich Western Australia is so deprived of good surf. However, this means Perth is an ideal place to learn, plus there is the added bonus of Rottnest Island, where some serious waves can be had, a short ferry ride from the city. Prior to two significant changes in sea level over 7,000 years ago, Rottnest was initially attached to the mainland. Local Aboriginal people knew the Island as 'Wadjemup', which has been suggested to have the meaning land across the water. The island was named in 1696 by the Dutch explorer Willem de Vlamingh, who called it 'Rottnest' (meaning 'rats nest'), mistaking the marsupial quokkas for huge rats.