Tourists cross the Titlis Cliff Walk in the Swiss Alps, the highest rope bridge in Europe, at an altitude of 9,977 feet on Dec. 12, in central Switzerland. The bridge, which crosses a 1,640 foot-deep abyss, will be officially opened on Dec. 15.

Related: Europe's highest suspension bridge opens in Swiss Alps

Slideshow: Winter Wonderland

Previously on PhotoBlog:

• Chugging along a snowy mountain
• Hiking among the clouds in Switzerland
• Rainbow arches over Switzerland's Lake Geneva
• Don't look down! Mechanics inspect sky-high cable car system

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