EXCLUSIVE: Robert Redford Can't Contain Himself in These Hilarious 'A Walk in the Woods' Bloopers

The veteran actor couldn't help but crack up on the set of his adventure comedy 'A Walk in the Woods.'

If this blooper reel from A Walk In the Woods is any indication, Robert Redford and Nick Nolte had a seriously fun time on the scenic set.

When you bring together Redford, a 79-year-old two-time Oscar winner, and Nolte, a 74-year-old star known for his tough guy gruffness, you might not expect tons of behind-the-scenes hilarity.

WATCH: Robert Redford Brings the Laughs With Nick Nolte in 'A Walk in the Woods'

ET has an exclusive look at the film's great gag reel, and it's clear that the laughs were both on screen and off -- and that Redford often has a hard time keeping his composure.

The film, based on famed travel writer Bill Bryson's memoir of the same name, tells the tale of two longtime friends who decided to leave their responsibilities behind and hike the Appalachian Trail for an adventure of a lifetime, and hijinks ensue.

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With Emma Thompson, Mary Steenbergen, Nick Offerman, and Kristen Schaal co-starring, it's no surprise that things got a little goofy during Redford and Nolte's outdoor adventure.

A Walk in the Woods comes out on DVD and Blu-ray Dec. 29.

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