A popular Yellowstone National Park attraction will remain closed to summer tourists as scientists monitor a rogue thermal pool that might blast again after a major explosion last July.

Biscuit Basin, a popular attraction among tourists that is usually packed with visitors has been sealed off from the public since a massive explosion in July, 2024, and will remain closed during the summer season.

Biscuit Basin, located just north of Old Faithful, erupted at around 10 in the morning last summer, sending a massive plume of boiling water and debris shooting into the sky – soaring hundreds of feet into the air.

The dramatic blast completely destroyed the wooden boardwalk and left tourists running for safety.

Miraculously, no one was injured but scientists call it one of the most powerful hydrothermal explosions in the area’s recorded history.

Now, given the basin’s unpredictable history, scientists are unsure when or if it will blast again. 

‘Since the July 23, 2024, explosion, Biscuit Basin has been closed to public visitation as Yellowstone National Park assesses damage and the potential for future hazardous events,’ a released stated by Yellowstone Volcano Observatory. 

‘We were fortunate that no one was injured during what was clearly a spectacular event,’ Mike Poland, scientist in charge of the Yellowstone Volcano Observatory told the Cowboy State Daily.

‘We don’t have enough information to know how Black Diamond pool is going to behave going forward,’ he added.

A popular Yellowstone National Park attraction will remain closed to summer tourists as scientists monitor a rogue thermal pool that might blast again after the major explosion last July

Biscuit Basin, a popular attraction among tourists that is usually packed with visitors has been sealed off from the public for the entire summer season following a massive explosion in July, 2024

‘We know from seismic data and eyewitnesses that there have been small bursts from Black Diamond Pool since the big explosion last July.’

‘The problem is that we don’t have any really good observations or documentation of these events, so that’s why we installed this webcam.’

The power behind these explosions comes from a deadly combination of superheated water and restricted underground plumbing that creates a pressure cooker effect beneath the earth’s surface.

Poland revealed that rocks blasted from the pool during July’s explosion showed evidence of being ‘cemented together’ by silica deposits that had been building up for years.

‘All of the rocks that we looked at that came out as part of that explosion showed evidence of being solidified,’ he told the outlet.

Biscuit Basin, located just north of Old Faithful, erupted at around 10 in the morning last summer, sending a massive plume of boiling water and debris shooting into the sky, soaring hundreds of feet into the air 

The dramatic blast completely destroyed the wooden boardwalk and left tourists running for safety

Miraculously no one was injured but scientists call it one of the most powerful hydrothermal explosions in the area’s recorded history

‘They were cemented together by silica deposited out of the hot water in Black Diamond Pool.’

This essentially created an underground cork that trapped enormous pressure until it finally gave way and ended with the massive explosion.

‘Silica is impermeable,’ he said. ‘When you build up a layer of silica, it acts like a container, sealing pressure in.’

‘That’s what happened to drive the explosion back in July. The pool sealed itself by depositing all the silica in areas, which allowed pressure to build and eventually generate the explosion.’

Last year’s explosion wasn’t the first at Black Diamond Pool.

On November 5, 2024, scientists collecting gas samples witnessed another violent outburst, while a winter tour group witnessed yet another eruption on January 3, 2025.

But last year’s was the largest in recorded history.

The terrifying power behind these explosions comes from a deadly combination of superheated water and restricted underground plumbing that creates a pressure cooker effect beneath the earth’s surface

‘The plumbing system was blown apart by that big event, but we still don’t understand what the plumbing system looks like now and how it might have evolved since that big event,’ Poland told the outlet.

‘That’s what the monitoring in the Biscuit Basin specifically aims to see.’