With 3 UNESCO sites Tasmania sure has it's fare share of walks and lookouts.
Tasmania Parks & Wildlife Service
http://www.parks.tas.gov.au/
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A very long day walk (or bike ride) from Darlington, or easily accessible from Frenchs Farm / Encampment Cove campgrounds. A fairly easy walk to a beautiful bay, which was a whaling site in the 1800s and is home to fairy penguins.
Mount Maria (711 m) is the highest point on the island, and offers sweeping views up and down the Tasmanian coast. The last part of the track goes up a scree slope with some clambering up (or down!) large boulders just before the summit.
This relaxing coastal walk on Maria Island becomes a stunning one once you reach its destination: the Painted Cliffs.
What these cliffs lack in height they more than make up for with their amazing colours and swirling patterns. The patterns are caused by ground water percolating down through the sandstone and staining the rock. Wave action and sea spray have continued the erosion, resulting in magical honeycomb patterns, potholes and notches.
The cliffs are best approached at lower tide levels, to allow safe access to the rock platform beneath the cliffs. They are especially brilliant towards sunset. Bring your camera!
Relax on Hopground Beach. Swim, snorkel and explore the rockpools of the Maria Island Marine Reserve.
Bicycles may be ridden on the formed road sections but not on beaches or walking tracks.
A very long day walk (or bike ride) from Darlington, or easily accessible in a day from Frenchs Farm / Encampment Cove campgrounds. The walk along a sandy track end at the Robeys Farm farmhouse, which is in pretty good condition and has a number of original artefacts inside the house.
This easy walk is sheltered from the coastal winds and provides a glimpse of Maria Island's wildlife and history. This walk is one of the best places to see the endangered forty-spotted pardalote. The walk takes you through open woodlands into tall eucalypt forest, and returns via ruins from the old cement works. The area near the reservoir is a good place for a picnic in the bush. Cycling is only permitted on Southern track due to safety.
A full-day hike (loop) past the Mount Mawson Ski Field, the summit of Naturalist Peak and Mount Field West. Great variation of vegetation and scenery along the way.
Mt Field National Park is Tasmania's oldest and most loved NP. The park has a wide variety of scenic features and wildlife and offers a great range of facilities for visitors. Few other National Parks in Australia offer such a diversity in vegetation, ranging from tall swamp gum forests and massive tree ferns at the base of the mountain. The park essentially has two visitor sections. The first, near the park entrance, includes picnic facilities and the famous Russell Falls. Stunning walks through enormous fern forests and some of the tallest trees in the world are available in this area.
Fairly easy walk within the grounds of Cradle Mountain Lodge. Walk around through rainforest to discover King Billy Pines up to 1,500 years of age.
Waldheim and Weindorfers Forest Walk: a 20 minute circuit starting from the historic Waldheim Chalet. A glimpse into Gustav Weindorfers's pioneering life at Cradle can be seen at Waldheim Chalet.
Picton Road is 16km unsealed (I got a flat tyre in a Toyota Corolla doing 30km/hr) . You park just before the landslide then its around a 3km walk to Farmhouse Creek.
From where you park the car to Cutting Camp is approximately 21km/8-10hrs with around 600m elevation gain. Plenty of mud and root climbing. you will climb under and over fallen trees.
I set up camp at Cutting Camp for 2 nights. There is plenty of water from Cherry Creek alongside the camp but you must treat it as there have been giardia cases.
Day two: climb 600m and about 3-4km 3-4hrs up to Bechervaise Plateau then another approximately 3hrs return to the summit.
If the weather is bad you will not be able to summit. You will need to be comfortable on things similar to Tibrogargan Caves Route.
After the relatively easy famous traverse above Lake Geeves there is a difficult bit to climb where getting up is much easier then getting down and there is zero margin for mistakes.
(Note this information is a guide and you will need to source addition information elsewhere)
(I will refine and add to this later)