Sky-high demand

At a heart-stopping 4,000 feet above the Colorado River’s bed, this open-air cantilever bridge extends 70ft out over the canyon.

The 10ft wide, horseshoe-shaped platform has attracted around 370,000 visitors per year. But for anyone who is nervous about walking out onto glass above the gaping 18-mile wide gorge, have no fear. The skywalk can hold the weight of 71 fully loaded Boeing 747 jets. grandcanyon west.com

This spectacular mountaintop viewing platform on Austria’s Stubai Glacier juts out over the surrounding peaks and valleys.

To reach it, take the Eisgratbahn and Schaufeljochbahn gondolas, which whisk passengers 10,531ft above sea level, then walk five minutes to the observation deck.

The red-brown steel platform soars 30ft high and out into the abyss. A telescope on the deck is free of charge. The nearby Jochdohle restaurant, perched at an altitude of 10,335ft, offers pretty amazing views too. tyrol.com