Warning: this video may make you cry.

Because it shows a group of chimpanzees experiencing the outdoors for the first time in 30 years.

The chimps - many of whom were kidnapped as babies - have been kept isolated in laboratories for decades. But now they've been rescued and rehoused at the Gut Aiderbichl animal sanctuary near Salzburg, Austria. This video shows the moment they first step out into the sunlight and take in their new freedom - and it's very moving indeed.

The clip has been out for a while, but is now going viral. And here's another great video, of the sanctuary's founder Michael Aufhauser - and renowned British primatologist Jane Goodall - celebrating the opening of the chimpanzee enclosure:

(Via Most Watched Today)

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