(3918, 61 km S, Mornington Peninsula Shire)
Located south of Hastings on the Westernport side of the Mornington Peninsula, this part rural and part residential district was surveyed as a parish in the 1860s. The name was presumably taken from the Australian bittern (Botaurus poiciloptilus) that inhabited nearby marshland. Reserves such as the Bittern Coastal Wetlands Boardwalk feature significant bushland and coastal vegetation. Selectors originally established the area as a fruit-growing district. When the Frankston-Stony Point railway line was inaugurated in 1889, Bittern opened as a station offering easy rail freight for local growers. But there was little else at Bittern until nearby Hann's Inlet was selected as the site of a Commonwealth Naval Base in 1911 and a store opened to service builders on the site. The establishment of BP's Westernport Refinery in 1966 also boosted the town's population and services.