The Roaring Forties whip through the park for much of the year, adding to the drama, and even the natural waterways are immense: Port Davey and Bathurst Harbour together are larger than Sydney Harbour.
One of the most visually spectacular drives in Australia on a clear day is the section of the road to Scotts Peak Dam that hugs the shores of Lake Pedder. The 24,200-hectare (60,000-acre) dam now sits like a massive stage in an amphitheatre created by the shard-like Mt Anne, Mt Eliza and Western Arthurs - the last a range of 22 major peaks crushed into a mere 15 kilometres (nine miles).
Dwarfed on all sides by this incredible landscape, you can only imagine the contrast that must once have been created by the broad pink beach and soft hues of the original Lake Pedder, whose inundation is now widely regretted by a more environmentally sensitive Tasmanian community.
Beyond its turnoff to Scotts Peak Dam, the main road into this northern section of the park (the Maydena end north-west of Hobart) continues to Strathgordon, past the aptly named Saw Back Range. At the end of the road is the 140-metre (460-foot) high Gordon Dam, a towering feat of engineering. You can walk across the dam wall from one side of the gorge to the other, and it's even possible to abseil down, under the supervision of a qualified guide. The view of the chasm from the wall is staggering - if you are afraid of heights, beware.
South of Hobart, a comparatively flat section of the park touches the idyllic Recherche Bay at Cockle Creek, which is the start of the South Coast Track and as far south as you can drive in Australia. Sections of the bay's foreshore that are not part of the national park have been protected from logging in recognition of their heritage value, including the remains of an 18th century garden and observatory established during early French exploration.
On a scenic flight from Hobart you will be astonished by how unremittingly rugged the park is. Its 608,000 hectares (1,502,400 acres) are noted for their virgin rainforest, tortuous horizontal scrub and stands of rare Huon pine. If you arrange for your flight to touch down at Melaleuca before returning to Hobart, you may even catch sight of the rare orange-bellied parrot from the specially constructed bird hide.
Bushwalkers on the Southcoast Track from Cockle Creek or the Port Davey Track from Lake Pedder - both long and arduous multi-day treks - can also arrange to be picked up by plane at Melaleuca, where a couple of hardy souls still mine alluvial tin. The only alternatives are to depart by sea or walk back out.
Other tough walks in the Southwest National Park are the Western Arthur Range, the Franklands Traverse and the climb to Federation Peak, all of which will bring you up against some of the most challenging terrain in Australia.
In addition to bushwalking, fishing is popular in this part of Tasmania. For 10 years or so after Lake Pedder's flooding, drowned vegetation became a source of aquatic nutrition so rich that it supported an unnaturally large population of trout, much to the delight of anglers. Stocks have since declined, but the fishing here and on Lake Gordon is still highly regarded. Make sure you have a fishing licence and only fish in-season (generally August to April).
Camp sites are located along both the Gordon River Road and Scotts Peak Road. These vary from very basic sites with no facilities to sites with toilets and tank water. Teds Beach has toilets and electric barbeques. Edgar Campground has toilets and fireplaces and firewood is provided. The Huon Campground has a shelter, composting toilets and fireplaces. There are no charges and bookings are not taken.
Mount Field National Park, which you pass on your way to the northern access to the Southwest National Park, has well developed campground facilities, including showers and powered sites.
Recherche Bay State Recreation Area has camp sites with toilets but without firewood or water at Gilhams Beach, Finns Beach and Catamaran River. Cockle Creek has a large camping area around Rocky Bay.
There are two walkers' huts at Melaleuca, as well as pit toilets and water. There are no other huts along either the Port Davey or the South Coast track.
Commercial accommodation is available at Strathgordon, Maydena and the town of National Park at the northern end and at Southport and Dover at the southern end.
On your way to the Maydena end of the Park you travel through the historic town of New Norfolk and its surrounding hop fields in the lush Derwent Valley. You also pass Mount Field National Park, which is described at length elsewhere in this section.
If you are not planning to bushwalk at the southern end of the park, you may enjoy combining that trip with a visit to Hastings Caves, just north of Southport.
The Southwest National Park is a 2.5 to three-hour drive from Hobart. Take the Lyell Highway (A10) to New Norfolk, then the B62 and B61 to Mount Field National Park and on to Maydena, which is the last stop for petrol before you enter the park. From here, the Gordon River Road (B61) will take you to Strathgordon and the dam. Alternatively, turn off the B61 and onto the Scotts Peak Dam Road at Frodshams Pass to reach the start of the Port Davey Track.
The southern end of the park is about two hours' drive from Hobart. Take the Southern Outlet (A6) to the Huon Highway (A6) through Geeveston to the Hastings Cave turnoff onto the C635 just north of Southport. Take the C635 beyond the next turnoff to Hastings Caves to the gravel C636 to Cockle Creek.
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