The ground here actually steams. Like, constantly. Not in some poetic metaphor kind of way—actual sulfurous vapor rising from cracks in the earth as if the planet itself needs a cigarette break.
When Lava Flows Decide Your Hiking Plans Better Than Any Trail Map
Hawaii Volcanoes National Park sprawls across 335,259 acres on the Big Island, and here’s the thing: roughly half of that didn’t exist 200 years ago. Kilauea, one of the world’s most active volcanoes, has been erupting pretty much nonstop since 1983—adding about 500 acres of new land to the island through 2018. Then in May 2018, the volcano decided to throw what geologists politely call a “lower East Rift Zone eruption,” which is code for “neighborhood-destroying lava fountains that reached heights of 300 feet.”
The park contains two active volcanoes: Kilauea and Mauna Loa.
What Nobody Tells You About Visiting an Active Geological Wound
Mauna Loa last erupted in November 2022, sending lava flows down its northeast flank for the first time since 1984. The eruption lasted twelve days. Standing at 13,681 feet, it’s the world’s largest active volcano by volume—18,000 cubic miles of rock that decided to camp out in the middle of the Pacific. Turns out you can drive to the summit area via a steep, winding road that makes your ears pop and your rental car wheeze, but most visitors stick to the Chain of Craters Road, which descends 3,700 feet over 19 miles before ending abruptly where lava flows consumed the pavement in the 1990s.
The road just stops. Buried under black rock that cooled into frozen waves.
Breathing Sulfur Dioxide Like It’s Your Job Because Technically It Is Now
The park’s air quality monitoring system tracks sulfur dioxide levels in real-time because vog—volcanic smog—isn’t just unpleasent; it’s legitimately hazardous for people with respiratory conditions. On bad days, the AQI (Air Quality Index) can spike above 150, which is when park rangers start closing sections. You’ll want to check the daily conditions at the Kilauea Visitor Center, which sits at 4,000 feet elevation and offers exhibits explaining why you’re coughing. Wait—maybe that’s just the altitude? No, it’s definitely the volcanic gases.
The Crater That Collapsed Into Itself and Took a Parking Lot With It
Halema’uma’u Crater, once home to a lava lake that glowed like earth’s own forge, collapsed spectacularly during the 2018 eruption. The crater floor dropped more than 1,500 feet, quadrupling the crater’s depth. The Jaggar Museum and Hawaiian Volcano Observatory, which had perched on the crater rim since 1927, became structurally unsound and closed permanently. By December 2020, lava returned to Halema’uma’u, filling the crater with a lake that sometimes reaches depths of 700 feet—a molten pool visible from overlooks along Crater Rim Drive, glowing orange at night like something from a disaster film except this is Tuesday.
Visitors can’t get as close as they used to. The old overlooks cracked and fell.
Why You Should Pack Like You’re Visiting Three Different Climates Because You Are
Temperature at sea level: 80°F. Temperature at the summit: 45°F. That’s a 35-degree swing within an hour’s drive, so layering isn’t optional—it’s survival strategy. The park receives between 95 inches of rain annually at higher elevations (creating actual rainforest with tree ferns that look prehistoric) while coastal sections get maybe 20 inches. Thurston Lava Tube, a 500-year-old tunnel formed by flowing lava, stays around 65°F year-round and drips with moisture from the rainforest above. You’ll walk through in ten minutes, emerging to birdsong from native honeycreepers—if you’re lucky, maybe an ‘apapane with its crimson plumage.
The park’s entrance fee is $30 per vehicle, valid for seven days. Rangers recommend arriving before 9 AM or after 5 PM to avoid crowds that clog the parking areas like tourists at a theme park, except this theme park occasionally closes sections due to active volcanic activity. Cell service is spotty. The nearest gas station sits in Volcano Village, eleven miles away.
Bring water. Bring snacks. Bring respect for the fact that Pele, the Hawaiian goddess of fire, still lives here in every steam vent and lava flow—at least according to cultural tradition that predates geology by centuries and honestly makes just as much sense when you’re standing on ground that’s literally being born.
