was undertaken in the Tower Hill Wildlife Reserve from 1961. Naming The origin of the English name, Tower Hill, is not certain. One source suggests that it arose in the 1840s owing to its resemblance to a castle, while another credits a sailor from Glasgow with "naming the site after Tower Hill in Scotland". Location The town of Koroit is on the north rim of Tower Hill, within easy reach of both Warrnambool and Port Fairy. The volcano is located about west of Melbourne and north-west of Warrnambool. Description Tower Hill's formation is known as a "nested maar", the largest of its type in Victoria. It was created by molten lava pushing its way up through the Earth's crust, before hitting a layer of water-bearing rock, which led to huge explosions. A shallow crater was left, later becoming a lake after it filled with rainwater. Subsequent to this, later eruptions occurred in the centre of this crater-lake, pushing up islands and cone-shaped hills, known as scoria cones. It is "one of the largest eruption points of the Pleistocene Newer Volcanics Province of Victoria". The main crater is by . Within the steep-walled tuff ring is a crater with a depth of over . Because of the complex nature of its formation and structure, and as one of the largest maars in the world, it is of great geological significance both nationally and internationally. Tower Hill volcano is roughly wide and high, and as a giant maar (volcanic explosion crater), it is of international and national geological significance. It has a gradient of between 10% to 80% at the higher points. Reserve Now part of the state park system as the Tower Hill Wildlife Reserve, the area had been used since European settlement for farming and stone quarrying. The area has been reforested with native flora, and repopulated with native fauna since 1961. Brown's Quarry Brown's Quarry, on the southern side, was created in about 1951, but since around 1977 has only been used for dumping clean landfill. there is debate about what to do with the site next. The owners of the quarry would like to fill the quarry and restore the vegetation, arguing that this would make the perimeter of the volcano safer and allow a walking track to be built around it (which is part of the Tower Hill master plan), but geologists say that the wall of