Южно-Австралийская автомагистраль Юго-Восточная (South Eastern Freeway)

Freeway in South Australia
the freeway in South Australia

South Eastern Freeway is a freeway in South Australia (SA). It is a part of the National Highway network linking the state capital cities of Adelaide, SA, and Melbourne, Victoria, and is signed as route M1. It carries traffic over the Adelaide Hills between Adelaide and the River Murray, near Murray Bridge, where it is connected via the Swanport Bridge to the Dukes Highway, which is the main road route to Victoria. It was formerly signposted as Princes Highway, which refers to the coastal route from Adelaide to Sydney via Melbourne. 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". South Eastern Freeway includes twin tube tunnels – the Heysen Tunnels – in the descent towards Adelaide, the first of their kind on the National Highway.

South Eastern Freeway commences at the intersection with Glen Osmond Road, Cross Road and Portrush Road in Glen Osmond, and heads southeast as a six lane, dual carriageway route. As it traverses across – and through, in one section, via the Heysen Tunnels – the Adelaide Hills, and due the fact the freeway is a major freight route, it also features arrester beds and concrete median barriers, with street lighting between Glen Osmond and Crafers. The freeway narrows to four lanes just before it bypasses Crafers, and continues in a south easterly direction, past Stirling, Hahndorf and Mount Barker, before narrowing further to a two lane, single carriageway, crossing the Murray River over the Swanport Bridge, to terminate just east of the crossing in Long Flat, south east of Murray Bridge.

Shortly after the Adelaide–Crafers section opened, several incidents involving semi trailers drew media attention to the road. While the previous Mount Barker Road was a notorious stretch, its dangers were well known; the new freeway presented the new challenge of a sustained continuous gradient with traffic lights at the bottom. Heavy vehicles with inadequate braking found it hard to slow down once they had exceeded a certain speed; this was made worse with brake failures. It took some time, and the addition of several warning signs prior to the descent, for heavy vehicles to become familiar with the freeway's characteristics. Semi trailers can be seen travelling as slow as 20–30 km/h downhill. In 2005 changeable electronic road signs were installed every 200 metres, so that the speed limit of the road can be adjusted from Transport SA headquarters in Adelaide. This has both improved safety for commuters, and emergency service workers like the Country Fire Service. In 2010 and 2011, after more incidents involving trucks having problems successfully braking down the hill, including one going into a bus stop, and another going straight through the intersection at the bottom, the government added new laws that any vehicle with 5 axles or more must stay in the left lane and must not exceed a 60 km/h limit from the interchange at Crafers to the old tollhouse. More safety cameras were installed in an attempt to ensure trucks abide by this new limit. Additional signs for the two arrester beds on the descent have been added, to encourage out of control drivers to use them as a safer alternative. In August 2014, another truck descending the hills collided with cars at the intersection of Glen Osmond Road. Two people were killed. A driver of a sewage truck lost control after passing the arrestor beds. The driver was a new employee, who had never driven a manual truck before, and had never driven any vehicle on this segment of road. Driver Darren Hicks was seriously injured and testified against employer Cleanaway at a criminal trial after being granted immunity. The prosecution, brought by Comcare, heard that the brakes on the vehicle were defective. In 2021 Cleanaway was convicted of eight charges under health and safety legislation.

The Adelaide end of South Eastern Freeway leads downhill to traffic lights at the intersection of Glen Osmond Road which continues northwest as route number A1 into the Adelaide city centre, Portrush Road north to bypass the city and towards Port Adelaide, and Cross Road which leads west towards the southern suburbs of Adelaide. The southeastern end of the freeway, near Murray Bridge, feeds onto the Swanport Bridge, a two lane, bridge over the River Murray, where it joins Princes Highway, a dual carriageway highway to Tailem Bend. At this point, Highway 1 becomes a two laned, two way scenic route which passes through many coastal towns of South Australia and Victoria. The National Highway continues to Melbourne as Dukes Highway (A8) from Tailem Bend to the Victorian border and beyond as Western Highway.