Mount Martha is a seaside suburb on the edge of wider Melbourne, Victoria, Australia 68 km south-east of Melbourne's central business district. Its local government area is the Shire of Mornington Peninsula. It is on the south-eastern shores of Port Phillip and offers a bathing beach. A boardwalk winds its way for more than 5 km along the Balcombe Creek, its North beach mouth to the Briars Historic Park. The suburb's highest point bears the area's name and reaches 160 m. The peak was named in 1836 after Captain William Hobson’s mother, Martha Jones.