Our first inkling this would not be just another noisy, fumy ride on a snowmobile was on the way up to the Mýrdalsjökull Glacier, when the Super Jeep ahead of us stalled in knee-deep snow. The second clue came at base camp, where we signed the customary liability waivers and spent half an hour gearing up in boots, coveralls, balaclavas, helmets and insulated gloves. Members of our group took turns snapping photos of each other in our spacesuit getups — goofy, sure, but totally appropriate given the otherworldly nature of the terrain we were about to cover.

After a quick safety and navigation demo — including practice in the all-important butt-shifting maneuver designed to help straighten a skidding vehicle — we set out for our tour of this snowcap covering Mt. Katla, one of Iceland’s highest peaks and a still-active volcano.

Following the first leaning curve and a quick assessment of the terrain (ice, snow and ice-coated snow), I stifled the urge to speed ahead of the pokey fellow traveler in line ahead of me. Instead, I gripped the throttle and brake handles more tightly and kept my eyes trained on the near distance in anticipation.

The views from atop one of the country’s volcanoes were spectacular: moments of sun punctuated by low-hanging clouds while glacial ice and snow whipped around us. The spacewalker outfits and heated seats and handgrips softened the journey, but this was clearly not your garden-variety ski resort-style groomed trail. A glacier is no place to mess around.

After half an hour of zipping up, down and around what began to feel like the top of the world, we arrived at our destination, a site overlooking Eyjafjallajökull (E-15 to most non-natives), the volcano that famously shut down European air traffic and caused havoc in spring 2010. Clouds obscured the view, but still. I pulled out my trusty point-and-shoot camera for a shot and found it, sadly, frozen.

The trip back, now that we were veterans, seemed less fraught with peril. After shedding our borrowed gear, we warmed ourselves and sat for a surprisingly delightful spread of Mediterranean fare in a cozy shack at base camp. On the way back to town in the Super Jeeps, we made a quick photo stop at one of Iceland’s many spectacular waterfalls.

Fire and ice: The two extremes defined — and continue to define — Iceland. They also create an ideal natural playground for adventure seekers. Taking a trip in a Super Jeep (a tricked-out, souped-up, four-wheel-drive vehicle that can carry up to 10 passengers and cross rivers, trudge through snow and negotiate jagged lava fields) to a snowmobile on a glacier is one of the tamer recreational options.

The island nation spreads out over just more than 100,000 square miles, much of it uninhabited, connected by one large ring road and, conveniently for tourists on a tight schedule, helicopters. The accessibility of Iceland’s natural wonders allows the visitor to sample environmental extremes within the span of one or two days. It’s the perfect opportunity to try something none of your friends has probably done.

Diving, for instance, probably isn’t top of mind when you think of the North Atlantic, but it’s a popular activity here. Juxtaposed between Europe and North America, Iceland sits atop two tectonic plates that separate the continents. The geological phenomenon yields fissures in the island’s lava because the land below is pulling in opposite directions. That location, Silfra, is considered one of the top sites among serious scuba divers because of its unusual nature and the water’s clarity. It’s also a great spot for snorkeling year-round.

Snorkeling in icy waters © ElliThor.com for Arctic adventures

Snorkeling in the warm blue waters of Hawaii or the Caribbean won’t prepare you for Silfra, which is part of Thingvellir National Park, a UNESCO World Heritage site. The water may be crystal clear, but it’s also icy cold — about 35 degrees Fahrenheit — and deep: some 60 feet at its shallowest point and up to 200 feet at its deepest. Fortunately, thermal wetsuits help make it bearable, and between the feeling of weightlessness in the calm, clear water and the stunning views, one quickly forgets about the cold and the depth.

A typical Silfra tour takes about 45 minutes — just enough time, given the frigid conditions. A light current carries snorkelers through the fissure, past a gorgeous rock formation enclosure called the Cathedral and, finally, into a lagoon. Because of the depths, this is not recommended as a do-it-yourself experience, but a number of operators conduct regular trips.

One adventure package combines Silfra’s underwater world with another outside-the-box activity: caving. Iceland is teeming with lava tubes, tunnels where hot lava carved a channel hardened with time. As you bend and crouch — and sometimes crawl — your way through the tube, you’re likely to see stalactites. On the tour, you’ll wear a hard hat outfitted with a headlamp for safety; some guides have a group turn off their headlamps and experience true darkness for a short time, something most people have never done. This is decidedly not the time to be claustrophobic.

Options for exploring Iceland’s fiery side are plentiful. Super Jeep trips traverse rugged scenery to the bases of volcanoes, and a moderately challenging hike crosses newly formed lava fields to reach some of the country’s youngest craters.

For bragging rights, few adventure options top a helicopter trip directly over a volcano. On a clear day, the view of Iceland from the air can be more breathtaking than from the ground, passing by newly formed coastal islands and some of the larger volcanoes and over lava fields, black ash and scoria deserts. One tour visits the central highlands of Landmannalaugar, where black lava ridges punctuate the green, red, yellow and orange mountains. It’s a photographer’s dream.

If you’ve always wanted to find out what it’s like to climb on ice, this is the place. Ice climbing and hiking are among the most popular sports in Iceland, and conditions are good for both year-round. Tour operators provide the equipment — typically crampons, safety harnesses, ice axes and helmets — and after a crash course in navigating the ice, off you go.

One trip explores Sólheimajökull, an outlet glacier promising awe-inspiring ice formations, sink holes and jagged ridges, with several chances to give climbing a shot — with expert supervision.

Finally, after all this activity, a soothing visit to Iceland’s biggest tourist spot, the Blue Lagoon, is a must. A soak in the geothermal seawater at the sprawling open-air spa complex, especially on a cold day, does wonders to restore sore muscles and tired bones. In-water massages and more traditional skin treatments are available as well.

INFO TO GO

International flights arrive at Keflavík International Airport (KEF), 31 miles southwest of Reykjavík. Arcanum Glacier Tours conducts two-hour snowmobile tours of Mýrdalsjökull Glacier year-round. Arctic Adventures plans anything from a half-day snorkeling trip to a five-day itinerary of glacier hiking, caving, ice climbing or other outdoor activities. Luxury Adventures specializes in customized itineraries. Iceland’s location, about five hours from the northeastern United States and a few hours from European gateways, makes it a convenient stopover for travelers to Europe, with the Blue Lagoon and other activities handy to Keflavík Airport.