Greg Toppo

USA TODAY

The world's longest pedestrian suspension bridge opened in Switzerland on Sunday, a ribbon-thin span nearly a third of a mile long that challenges hikers to proceed in places at nearly 28 stories above ground.

Officials in the south of Switzerland unveiled the bridge after just 10 weeks of construction. It measures 1,620 feet long and rises as high as 278 feet above the Grabengufer ravine.

The span is also impossibly narrow, at just 25.6 inches wide.

See for yourself:

A drone's-eye view

The new bridge replaces one that was damaged by rock falls, the BBC reported.

The steel structure connects two sections of a trail between Grächen and Zermatt, a popular two-day hike. The local tourist authority warns that the high bridge is “for hikers with no fear of heights.”

The bridge completes a section of the Europaweg trail, a high-altitude hiking route that offers views of some of Switzerland’s highest peaks, including the Matterhorn.

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