Many suburbs of Melbourne are on the coastline of Port Phillip Bay.
Port Phillip Bay is separated from Bass Strait by the Bellarine Peninsula to the southwest and Mornington Peninsula to the southeast. It is one of the largest inland bays in Australia. The narrow entrance to the bay (the Rip) between Point Lonsdale and Point Nepean, features strong tidal streams. Large ships require expert local guidance to enter and exit, provided by the Port Phillip Sea Pilots.
The eastern side of the bay has sandy beaches extending from St Kilda, Sandringham, Beaumaris, Carrum, and down the Mornington Peninsula to Frankston, Safety Beach/Dromana and Rye to Portsea. Longshore drift carries sand from south to north during winter and from north to south during summer. Cliff erosion control has often resulted in sand starvation, necessitating offshore dredging to replenish the beach. On the western side of the bay there is a greater variety of beach types, seen at Queenscliff, St Leonards, Indented Head, Portarlington, and Eastern Beach.