On New Year's Eve, a 22-acre (9-hectare) chunk of Hawaii's famous Kamokuna lava delta collapsed into the ocean, triggering huge waves and showers of volcanic rock, and almost taking five tourists with it.

The Kamokuna lava delta is formed where lava spewing out of the Big Island's Kīlauea volcano meets the Pacific Ocean and rapidly cools, forming new land.

It's a popular tourist spot, but, as you can see in the crazy footage below, the striking black cliff that the lava flow forms isn't very stable. This footage shows only part of the delta collapse, which continued into the night as the waves washed away more of the cliff face:

The entire Kamokuna ocean entry lava delta was only 26 acres (10.5 hectares), which means a whole chunk of it is now lost to the ocean, including the tourist viewing platform.

The area - including the air space 1,000 feet (304 metres) above the delta - has now been temporarily closed, while the US National Park Service secures the region.

"Fortunately, there were no aircraft or boats reported in the area at the time of the collapse, nor were any visitors on the delta itself, which is closed for public safety," said Park Superintendent Cindy Orlando.

"Had anyone been close by on land, water or air, lives would have surely been lost."

Lava deltas are known for being pretty dangerous places to hang out. The Kīlauea volcano has been erupting steadily since 1983, but the new land formed by the cooling lava is built on unstable sand and substrate, which makes it incredibly susceptible to collapse.

Not only that, but as the lava enters the ocean, it produces a highly corrosive plume of hydrochloric acid and volcanic particles, which means it's always a pretty risky place for tourists to visit.

But it's uncommon for so much of the delta to fall away over a few hours.

The collapse began around 2 pm Hawaiian time on New Year's Eve, causing officials to shut off the viewing platform and monitor the situation. But at 7pm, five tourists ducked beneath the closure line to check out the cliff, ignoring warnings.

Around 15 minutes after a ranger retrieved them, the section of cliff they were standing on crashed into the ocean.

"It was a really close brush with death for them," said eruption crew ranger Travis Delimont. "Luckily, they finally listened to us and turned around in time."

As dangerous as the area is at this time, all that churning ocean and lava has actually created an incredibly beautiful phenomenon. The owner of Epic Lava Tours, John Tarson, captured this footage of the delta on January 2:

It's pretty incredible. But let's enjoy that raging natural beauty from behind the safety of our computers until the area's stable again, shall we?