Tourists accused of 'thermal trespassing' over 177C Yellowstone geyser

The tourists, who have not been identified, will appear in Wyoming court in December. Photo / Supplied

Two tourists were arrested for getting perilously close to a boiling geothermal geyser at Wyoming's Yellowstone National Park.

The pair were caught trying to get a closer look at the Old Faithful geyser.

Talking to KRTV the National Park Services said that the tourists were found "dangerously close" to the spout which emits jets of 177C steam.

According to Fox News the pair were charged with the peculiarly specific crime of "thermal trespassing". They will face a court over their actions in December.

Two tourists have been arrested after getting too close to a geyser at Yellowstone National Park. Photo / Supplied

"My family and I just couldn't believe what was happening," bystander Kimberly Guilliams told ABC News.

"They just didn't care and we couldn't believe that they thought that was OK."

Though National Park land, the thermal area around the geyser cordoned off by barriers and the danger was well signposted.

"I don't see how anyone couldn't be aware of the rules," she said. "They're posted everywhere. They're in multiple different languages.

"All around the border of the geyser, there are rules saying that it is very dangerous, that the ground is unstable and very fragile."

Old Faithful is a natural treasure, roughly the size of the Pōhutu geyser at Te Puia. However the regularity with which it erupts in a 30 metre spout of boiling water has given it the reliable moniker.

Kiwi Hamish McNab Campbell Cross was found to have tresspassed at the Grand Prismatic Spring in Yellowstone. Photo / Supplied

It erupts around 20 times a day, which has made it a popular attraction.

"Thermal area safety is an extremely important part of any trip to Yellowstone," said a park spokesperson in a statement following the incident.

"We ask visitors to take the Yellowstone Pledge before coming to the park and to read the park Visitor Guide for more information on safety, rules and regulations.

"Detailed information can also be found on the Yellowstone National Park app which will operate without cell service as long as it is downloaded before entering the park."

Kiwi Alexey Lyakh has was identified as one of four men who were videoed tresspassing in Yellowstone in 2016. Photo / Supplied

In 2016 two New Zealand tourists were identified among a group of tourists found trespassing in the Yellowstone thermal area, after posting pictures on social media.

Thermal areas are a draw to tourists internationally and many visitors are not fully aware of the dangers.

In 2010 a 10-year-old boy died after falling into a pool of boiling mud at Kuirau Park, Rotorua. He fell into the pool on Boxing Day 2010, and died four days later from his burns.

Recently a video emerged showing a pair of tourists trespassing at the Wai-O-Tapu thermal area, having passed warning signs to pose for photographs.

Although the tourists were unharmed and no charges were placed, their behaviour was widely condemned.