If you suffer from vertigo, these are ten destinations you should pass.
1Dachstein Sky Walk (Austria)
Nicknamed the "balcony of the Alps," the Dachstein Sky Walk is formally enthroned at 2,700 m above sea-level, high up on the 250 m vertical rock face of the Hunerkogel. A 360 degree panorama allows the visitor a view of Slovenia in the south to the Czech Republic in the north. The Sky Walk is distinctly higher than the platforms of the Niagara Falls or even the one at the Iguazu waterfalls in Brazil.
2Aurland Lookout (Norway)
Architects Todd Saunders and Tommie Wilhelmsen were commissioned to design a scenic rest-stop 2'000ft above Aurland fjord in Norway and came up with this beauty wining the first prize in Norwegian tourist routes competition. The outermost end of the horizontal platform - which curves to form the structure's support - is closed off by a sheet of glass, offering an incredible view towards the ground for all those with the guts to make the trip to the end.
3Grand Canyon Skywalk (Arizona - USA)
This horseshoe-shaped pant-filler hangs approximately 4,000ft above the floor and extends 65ft beyond the edge of the Grand Canyon. The horseshoe shaped skywalk is constructed of glass walls 4 inches thick and visitors must don special scratch-proof socks as they partake in the view. The work is a true engineering feat that can hold up to 70 tons (roughly 14 African elephants) and withstands winds of 100mph.
4Suspended platform at Iguazu Falls (Brazil and Argentina)
While the falls themselves are magnificent, their setting in a huge subtropical nature reserve makes visiting even more enjoyable.
To fully appreciate their size and splendor it's worthwhile viewing the falls from the skywalk. The viewing platform is so close you are instantly drenched by spray and deafened by the roar of water plunging over an 80 metre cliff.
5Auckland's Sky Tower (New Zealand)
Auckland's 328m Sky Tower is the southern hemisphere's tallest structure. It took 2000 tonnes of reinforcing steel, 660 tonnes of structural steel and 15,000 cubic metres of concrete to erect it. It can withstand 200km/h winds, earthquakes up to eight on the Richter scale and on a clear day, visibility is around 82km. The highest indoor point is Sky Deck, which has seamless glass giving unimpeded 360º views.
6Illawarra Fly Tree Top Walk (Australia)
This walk opened recently after five months of construction. Located at Knights Hill up high on the escarpment near Robertson in the Southern Highlands, the Illawarra Fly Tree Top Walk allows visitors to walk among the rainforest canopy 25 metres above the ground on a steel platform. The 500m elevated walkway features cantilever arms that take visitors to the edge of the escarpment and offer inspiring views of the coastline from Kiama through to Shellharbour.
7Landscape Promontory (Switzerland)
The landscape promontory is a suspended viewing platform designed by Paolo Bürgi as part of the Cardada project, a revitalization of the Cardada mountain that is expected to finish in 2010. The passageway made of steel and titanium leads to the lookout platform with a view of Lago Maggiore. The landscape panorama is not the only thing that visitors are meant to appreciate. Symbols in the paving with accompanying texts in the railing provide references to history and literature.
8Infinity Room at House on the Rock (Wisconsin - USA)
The House on the Rock, originally opened in 1959, is a complex of architecturally unique rooms, streets, gardens and shops designed by Alex Jordan, Jr. It is located in Spring Green, Wisconsin, and is a regional tourist attraction. The Infinity Room at the House extends several hundred feet over the valley, without supports underneath, and is lined with over 3000 handmade windows.
9Il binocolo (Italy)
Within the gardens of Trauttmansdorff castle in Italy you'll find this charming steel platform poking out through the trees, its name (meaning 'the binoculars') coming from the shape of the platform's small roof and the view of the surrounding landscape. Designed by architect Matteo Thun.
10Top of Tyrol (Austria)
Top of Tyrol by Astearchitecture is a viewing platform located 3,000 m above sea level at the Stubai Glacier in Tyrol, Austria. Weathering steel was used in the construction of this structure to account for the extreme weather conditions so you can stand 9 metres away from the mountain with a perfect view of Stubai glacier.