Video has captured the moment visitors to a nature reserve crossed the path of a giant alligator.

Kim Joiner was within metres of the animal at Circle B Bar Reserve in Florida, and was quick enough to reach for her camera.

“I saw it coming.” Ms Joiner said in a post on Facebook.

“I have been more scared when they just cross with no warning on Alligator Alley Trail. I love Circle B. Nature at its best.”

The alligator is believed to be over 12 feet long and weigh around 800 pounds.

Although some had questioned the authenticity of the video, police confirmed the animal was real.

Locals had previously nicknamed the animal “Big Humpback”, claiming he had been around for years.