The Mount Lofty Ranges go from the south tip of the Fleurieu Peninsula at Cape Jervis and stretch north for more than 300km (190mi). They end north of a town called Peterborough. Near Adelaide, these mountains separate the Adelaide Plains from the large flat areas around the Murray River that go east to Victoria.
The Heysen Trail, a long walking path, goes almost all the way along the mountains. It crosses west to the Flinders Ranges near a place called Hallett..
The mountain ranges have a Mediterranean climate. This means they get medium rain from winds that come from the southwest. Summers are hot, and winters are cool. The southern part of the mountains gets more rain (about 900mm (35in) each year) than the northern part (about 400mm (16in)).
Southern ranges
Unusual gold specimen from the old Victoria Gold Mine, probably the first gold mine worked in Australia, near Castambul.
Many wineries are in the ranges. The Barossa Valley and McLaren Vale are famous wine regions. Grapes are also grown in the Adelaide Hills and Onkaparinga Valley.
There are no big mines working in the southern ranges now, but there are many old mines. One was an iron sulfide mine at Brukunga,, which worked from 1955 to 1972. It helped make fertilizer for farming after World War II but caused pollution that people are still trying to fix.
A small silver and lead mine at Glen Osmond was the first metal mine in South Australia and all of Australia. It opened just two years after the state was founded in 1836. South Australia did not have a big gold rush like other states, but gold was mined near Echunga and Williamstown in the Barossa. Other old mines include a silver-lead mine at Talisker near Cape Jervis and a limestone mine at Rapid Bay, which closed recently. Copper was mined at Kapunda, Truro and Kanmantoo and might be mined again. There is also a plan for a zinc, lead, silver, and gold mine near Strathalbyn. Many quarries are in the ranges, especially in the Adelaide foothills. These quarries gave the quartzite stone used in the old sandstone buildings in Adelaide.
Today, only one railway goes through the Mount Lofty Ranges. It is the main railway line between Adelaide and Melbourne. This railway was built in the 1870s and has only had small changes since then. One big change was making a new tunnel at Sleeps Hill.
In the past, passenger trains ran from Adelaide to Bridgewater, which is in the middle of the hills and ranges. Now, trains only go as far as Belair, which is in the foothills. There used to be a railway near Willunga, but it was closed and taken away in the 1960s. That old railway path is now a cycling trail. The Victor Harbor railway line goes around the east side of the ranges and is now used as to run old trains for visitors.
Northern ranges
The northern ranges are sometimes mixed up with the southern Flinders Ranges. They are also called the "Mid-North ranges" or "central hill country." These hills go from near Kapunda in the south to dry hills past Peterborough in the northeast. The tallest mountain here, and in all the Mount Lofty Ranges, is Mount Bryan, which is (936m or 3,071ft) high. Other important hills are (714m or 2,343ft) and Stein Hill (605m or 1,985ft which looks over the town of Burra.Burra.
Mining used to be very important in the northern ranges but is not done there now. The copper mine at Kapunda, just north of the Barossa Valley, worked from 1842 to 1877 and helped the young state’s economy. But it was soon less important than the big mine at Burra, further north. The Burra mine worked from 1845 to 1877 with some breaks. Later, bigger mines opened on the Yorke Peninsula. Because there was so much copper at Burra, the mine opened again as an open-cut mine in 1971 but closed ten years later.
The Clare Valley is in a small valley in the northern Mount Lofty Ranges, just southwest of Burra. It is a famous wine area and a popular place for people from Adelaide to visit on weekends. It also has the only conservation park in the northern ranges, called Spring Gully.
At the northern end of the ranges, there are two interesting places. One is a small town called Yongala, known for being the coldest place in South Australia because it is 100km (62mi) inland and on a high flat area like much of the Mid North. The other is a place near Orroroo called "Magnetic Hill." This name comes from an optical illusion that makes it look like cars roll uphill.
The Mount Lofty Ranges are part of a larger area called the Adelaide Rift Complex. The southern part of the ranges and the slopes of Mount Lofty that look over the Adelaide Plains have been broken by block faults to form a shape called a half-graben. When you look at the ranges from the beach or the city, they look like steps. Because of this, they were once called "The Tiers."
There are several big faults (cracks in the earth) in the Adelaide area. These faults run from northeast to southwest and create different blocks of land:
Para Fault: This fault goes from Gawler in the north, through Elizabeth, and then disappears under newer soil in the northern suburbs. The steep edge made by this fault is covered with houses in the northern suburbs (Para Hills). The town of Gawler sits at the base of this fault where the South Para River comes out of the ranges. Closer to the city, this edge is less clear and hard to see near North Adelaide.
Eden-Burnside Fault Zone: This is a group of faults at the base of the main steep edge of the Adelaide Hills. It separates the young (Quaternary) soil of the plains from the old (Proterozoic) rocks of the ranges. It starts near One Tree Hill in the northern suburbs and runs about 30km (19mi) in a curved line to the sea at Marino. This edge is called the "Hills Face Zone" and has special rules to protect it. Houses here are very expensive because of the great views. Many people want to keep the green hills as a background to the plains. Several creeks cut deep into this edge. One creek, Glen Osmond Creek, is where the main road east out of Adelaide (the South Eastern Freeway) goes. Only a few other big roads go up this steep edge.
Kitchener Fault: This long fault is a bit east of the Eden-Burnside Fault. It runs from north of the Barossa Valley past the Torrens gorge and meets the Eden Fault near Greenhill. You can see the fault edge near Williamstown and Kersbrook.
Clarendon Fault: This fault runs mostly parallel to the Eden-Burnside Fault. It forms the steep edge in Belair National Park and runs southeast to make the eastern border of the southern suburbs. It ends at Old Noarlunga, where the Onkaparinga River comes out of the ranges. Another steep edge from this fault forms the upper part of Mount Lofty, including Measdays Hill and Mount Lofty itself.
Willunga Fault: This fault is south of the Clarendon Fault and is the southernmost fault. The steep edge it forms starts in Scott Creek Conservation Park and runs southwest. Mount Bold Reservoir is where the Onkaparinga River is dammed in this edge. The towns of Kangarilla and Willunga are in valleys of this steep edge. The bare and dramatic face of "The Range" (also called Sellicks Hill Range) meets the sea at Sellicks Beach.
Bremer and Palmer Fault Zones: These faults are on the east side of the Mount Lofty Ranges. They make even steeper edges because there is less vegetation. The Palmer Fault Zone marks the edge of very old rocks called the Kanmantoo group. To the east are younger soils from the Murray River. Towns like Palmer, Sedan, and Cambrai are at the base of these steep edges.
All these faults are still active today, and small earthquakes happen often. Big earthquakes in the southern ranges are rare. The last big one was the 1954 Adelaide earthquake on March 1, which was 5.5 on the Richter scale.
Another important part of Adelaide’s geology is the Tertiary marine sand deposits. These are old sand layers from the sea that have been dug up a lot. One big sand deposit is near the northern suburb of Golden Grove, and another is near McLaren Vale.
Ecology
Mount Lofty Botanic GardenMount Lofty Botanic Garden Lake
Plants
The natural plants on the mountainsides are mostly eucalyptus trees mixed with golden wattleacacia trees on the lower slopes. There are also many small bushes and herbs growing under the trees. Some special orchids that only grow here can be found. Similar plants grow on Kangaroo Island, which is part of the Mount Lofty woodlands area recognized by the World Wildlife Fund.
Many plants and animals have been lost in the ranges because the woodlands have been cleared. The hillsides have mostly been cleared for growing fruit and other farming. The city of Adelaide has also grown on the lower slopes, causing loss of homes for animals. Some animals have disappeared from the area, including all types of bettong and quoll marsupials, and birds like the regent honeyeater (Xanthomyza phrygia), swift parrot (Lathamus discolor), king quail (Coturnix chinensis), brown quail (C. ypsilophora), and azure kingfisher (Alcedo azurea). Clearing land and farming still happen, and grazing animals damage the habitats. Introduced animals like cats, foxes, and rabbits also harm the wildlife and their homes. Protected areas are usually small and broken into pieces.
