You can actually see this circus lion's face light up the moment he knows he's free.

This big cat named Will was freed from a tiny cage where he'd been housed for 13 years. When he stepped into the grassy enclosure at Brazil's Rancho do Gnomos wildlife sanctuary, he kicked up a dust cloud, pawing at the ground and rolled around in the grass.

The sanctuary's staff believe it was the first time the lion had ever felt grass under his paws.

The video of Will's release was shot in 2006, but the sanctuary just published it on Facebook this week.

The sanctuary's founder Marco Pompeo says Will passed away from natural causes in 2011, but he had five great years of freedom — in the company of other lions — after he arrived at Ranco do Gnomos.

"He loved to lie in grass and look at the sky," Pompeo told The Dodo. "He was a very happy lion."

(WATCH the video below)

Story tip Denny Hall

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