Travelers will soon be able to walk across the world's longest and highest glass-bottom bridge, which spans two cliffs in China's Hunan province.

This week, workers were photographed installing the bridge's first piece of glass.

Set against dramatic landscapes in Zhangjiajie National Forest Park, the bridge is 430 meters long, six meters wide and hovers over a 300-meter vertical drop.

Construction on the bridge was originally expected to be finished at the end of 2015.

It's now set to open in May this year.