Question: The Heysen Tunnels are twin tube road tunnels which carry the South Eastern Freeway under Eagle On The Hill in the Mount Lofty Ranges in South Australia, Eagle On The Hill is an unbounded locality of which capital city in the Adelaide Foothills?
Context: Mount Lofty Ranges zone is a wine zone located in central South Australia west of the Murray River that occupies the Adelaide metropolitan area north of Glenelg, extending as far north as Crystal Brook, and as far south as Mount Compass in the Mount Lofty Ranges.  The zone which encloses the Barossa zone on three sides, consists of the following wine regions all of which have received appellation as an Australian Geographical Indication (AGI): Adelaide Hills, Adelaide Plains and Clare Valley.  The zone received AGI in 1996. Eagle On The Hill is an unbounded locality of Adelaide in the Adelaide Foothills.  It borders Mount Osmond and Waterfall Gully. Mount Osmond is a small suburb of 2,497 people in the South Australian capital city of Adelaide.  It is part of the City of Burnside local government area and located in the foothills of the Adelaide Hills, five kilometres south east of the city centre.  The suburb is high on the hill of the same name, which is the last hill on the right when approaching Adelaide down the South Eastern Freeway before the road levels out onto the Adelaide Plains.  It is bounded to the north by the suburb of Beaumont, to the north-east by Burnside, to the east by Waterfall Gully, to the south by Leawood Gardens/Eagle On The Hill, to the south-west by Urrbrae, to the west by Glen Osmond and to the north-west by St Georges. Leawood Gardens is a small suburb of Adelaide, South Australia in both the City of Mitcham and the City of Burnside located in the foothills of the Adelaide Hills.  It is crossed by both the South Eastern Freeway and Mount Barker Road uphill from the "Devil's Elbow" intersection, and contains the northern portal of the Heysen Tunnels. Aldermanite is a rare hydrated phosphate mineral with formula MgAl(PO)(OH)·32HO.  It's named after Arthur Richard Alderman (1901–1980), Professor of Geology and Mineralogy, University of Adelaide.  Its type locality is Moculta Phosphate Quarry (Klemm's Quarry), Angaston, Barossa Valley, North Mount Lofty Ranges, Mount Lofty Ranges, South Australia, Australia. Mount Barker Road was once the main road from Adelaide through the Adelaide Hills to Mount Barker on the eastern slopes of the Mount Lofty Ranges.  The main route has now been replaced by part of the South Eastern Freeway, but most of it remains in some form.  The remaining sections of Mount Barker Road are still classified as state roads. The Heysen Tunnels are twin tube road tunnels which carry the South Eastern Freeway under Eagle On The Hill in the Mount Lofty Ranges in South Australia.  The tunnels were excavated using a tunnelling machine normally used in heavy-duty mining operations which tunnelled through 500 m of rock for each tunnel at an average rate of 3 m per day.  The tunnels were completed in 1998 and officially opened in May 2000.  Each tunnel carries 3 lanes of traffic.  On average, they carry a total of 45,700 vehicles per day.  The maximum height of vehicles permitted in the tunnels is 5.3 m , the same as the Crafers and Mt Osmond interchanges.  Laser height detectors monitor traffic to provide warnings to drivers before they attempt to enter the tunnel. Totness Recreation Park, is a protected area located in South Australia within the localities of Mount Barker and Totness in the central Mount Lofty Ranges.  Covering 41 ha of land, the park is divided by the South Eastern Freeway and features a large dam.  It was declared as a reserve in 1970 and re-designated as a recreation park in 1972.  The park has no visitor facilities except for access tracks.  It is the only park in the district, managed by the Department of Environment, Water and Natural Resources, that is solely designated for recreation. The South Eastern Freeway (previously signposted as Princes Highway) is a 76 kilometre controlled-access highway in South Australia.  It carries traffic over the Adelaide Hills between Adelaide and the River Murray, near Murray Bridge, connecting via the Swanport Bridge to the Dukes Highway which is the main road route to Victoria.  It is often referred to by South Australians simply as "the Freeway", as it was the first freeway in South Australia, and is still the longest, and the only one with "Freeway" in its name rather than "Expressway" or "Highway".  It is a part of the National Highway network linking the state capital cities Adelaide to Melbourne and signed as National Highway M1.  The South Eastern Freeway includes 500-metre-long twin-tube tunnels (the Heysen Tunnels) in the descent towards Adelaide, the first of their kind on the National Highway.  It is designated as the M1. South Australia is an Australian state, situated in the southern central part of the country, and featuring some low-lying mountain ranges, the most significant being the Mount Lofty Ranges, which extend into the state's capital city, Adelaide, which comprises most of the state's population.  Adelaide is situated on the eastern shores of Gulf St Vincent, on the Adelaide Plains, north of the Fleurieu Peninsula, between Gulf St Vincent and the low-lying Mount Lofty Ranges.  The state of South Australia, which stretches along the coast of the continent and has boundaries with every other state in Australia, with the exception of the Australian Capital Territory and Tasmania.  The Western Australia border has a history with South Australia, involving the South Australian Government Astronomer, Dodwell and the Western Australian Government Astronomer, Curlewis in the 1920s to mark the border on the ground.
Answer: Adelaide