In 1872, a vast swathe of Wyoming, Montana and Idaho was set aside to create the first national park. Today, Yellowstone is more than just a wild gem – it’s the story of US conservation.

As the frigid night wore on, the thin whine of a lone coyote howling in the distance competed with the sound of vacuous gusts of wind. I wiped the moisture from my bedroom window and peered outside, but there was zero visibility due to an unseasonable and unexpected storm. By morning, the trees bowed under the burden of a sparkling white blanket. The leaden sky indicated temperatures were still at freezing, but at least the roads had reopened after two days of closure.

My introduction to the Wyoming side of Yellowstone National Park, a vast volcanic land that spills across two other states (Montana and Idaho), was proving that nature cares little for our plans. But, exactly 150 years ago, plans were what secured the future of this area and others across the country. In 1872, Ulysses S Grant, the 18th President of the United States, set aside the bulk of the 8,991 sq km that now make up Yellowstone. He wanted to secure this tapestry of prehistoric and historic cultural resources in perpetuity for the American people. In doing so, the first national park in the USA – and the world – was born. Today the US park system manages an area roughly equivalent to the size of Germany. Now, as the roads cleared, I could finally discover Grant’s wilderness legacy for myself.

After an hour’s drive, I arrived at the Norris Geyser Basin, the oldest of the park’s many geothermal areas and christened after Yellowstone’s second superintendent, a bullish pioneer-type named Philetus W Norris, who took the park in hand in 1877. Much of the basic ‘road’ system he laid out remains in the form of the Grand Loop Road. He also spent years documenting the hydrothermal features that now bear his name. I parked nearby and began gingerly descending an incline slick with hardened ice, muttering a soft expletive as I just about avoided ending up on my backside.

It was when I dusted the icy particles from my glasses that I saw a scene that could only be likened to the setting for a sci-fi film. A vast smoking expanse was punctuated by scorched lodge pole pines, boiling pools of water and surreal neon-coloured ponds of turquoise, bright red, shrieking yellow and emerald green. A boardwalk encircled the spectacle and shadowy figures moved along its path, obliterated by billowing steam. Except for snippets of quiet, masked conversation, an eerie silence smothered the area.

Looking down, I could see a thin, crusty layer of rhyolite that covered bubbling molten magma not far beneath the surface. Moisture from rain or melted snow that had trickled down through the sand hissed back to the top as super-heated sulphurous water. All of these features are the product of a vast caldera pushing, expanding and interacting with the land, often producing spectacular activity.

The Norris basin stretches for around 15 sq km, but it’s just one of many. To the south, the Upper Geyser Basin is best known for Old Faithful, which explodes in 50m-high showers of water about every four minutes, while Midway is the site of the psychedelic Grand Prismatic Spring. The whole park sits atop one giant supervolcano, and while Yellowstone may not have had a major eruption for over 640,000 years, it is both active and monitored closely. It felt strange to think that I was standing atop something akin to a geological A-bomb – and a colourful one at that.

The first thing you notice about the steaming pots and pools are the crazy kaleidoscope of hues. These are created by single-celled organisms called thermophiles (heat-loving creatures) that happily survive in incredibly hot temperatures. Recently, heat-adapted sponges were discovered at the bottom of the cold, deep Lake Yellowstone amid fields of vents, craters and gas-filled domes. Life finds a way.