Southwest National Park is an Australian national park located in the south-west of Tasmania, bounded by the Franklin-Gordon Wild Rivers National Park to the north and the Hartz Mountains National Park to the east. It is a part of a chain of national parks and state reserves that make up the Tasmanian Wilderness World Heritage Area. Covering an areā¦Southwest National Park is an Australian national park located in the south-west of Tasmania, bounded by the Franklin-Gordon Wild Rivers National Park to the north and the Hartz Mountains National Park to the east. It is a part of a chain of national parks and state reserves that make up the Tasmanian Wilderness World Heritage Area. Covering an area of 6,183 km², it is Tasmania's largest national park.