For the last few years, it seemed any time a photo caught my eye, it was of Iceland. I'd underestimated the country's beauty, a characteristic that helped it claim the No. 1 spot on our list of must-see international travel destinations for 2015.

So I made the nearly 3,000-mile journey from Chicago, reserving my first night in Iceland for the thing I was most excited for and one of the best things to do in Iceland: seeing the northern lights. The skies were clear on the Reykjanes Peninsula coastline that night, but our tour guide warned us that there was no guarantee the borealis would appear. I brushed her off at first, astounded by how brightly the stars twinkled against the night sky. Four hours of bone-chilling cold later, the darkness seemed to mock our search.

Around 1 a.m., just as our guide was calling it quits, the northern lights suddenly appeared, impossibly grand in a sky that had been black just moments before. It was remarkable—emerald plumes tinged with ruby, dancing at a tempo the eye could just barely keep pace with.

If you're set on seeing the northern lights and finding other great things to do in Iceland—and if you're really itching to get there, there's currently a Groupon Getaways deal to Reykjavik to be had—here are my top five picks, along with tips for once you're there and suggestions on how you can get a taste of each experience before you even head out on your trip.

1. See the northern lights.

Tip: Seriously, be patient. And bring a good camera.

If the Aurora Borealis are the impetus for your trip to Iceland, you might be wondering best times to see the northern lights are. Visit between late September and mid-April, when they're most visible. It's best to take a northern-lights excursion your first night in Iceland—that way, if the lights are a no-show, you'll have time to try again.

Most of the vantage points are coastal, leaving you at the mercy of soul-chilling winds. But the clear night sky and salty sea air set a beautiful scene; dress in warm clothes so you can enjoy it. You might even want to bring a blanket and a bottle of wine for extra warmth, and a book or a travel telescope to help pass the time. (Remember, it can take hours!)

One last thing: while the northern lights are naturally breathtaking, the human eye is incapable of seeing them as clearly and colorfully as they appear in photos. If you want to capture the borealis in its full glory, bring a DSLR camera or trade email addresses with someone who did.

Check out the Groupon Goods inventory of telescopes to start your star-gazing early.

2. Swim at the Blue Lagoon.

Tip: Book an in-lagoon massage, one of the most baller things to do in Iceland (or anywhere else).

Iceland claims two of National Geographic's 25 wonders of the world. One is the northern lights. The other is Blue Lagoon, a geothermal lagoon dug out of an expanse of volcanic rock.

I've never felt like more of a boss than I did on the day I spent at Blue Lagoon. It began with an in-water massage I'd prebooked via email. The service was less expensive than at many other destination spas, and took place in a dang lagoon. I highly recommend it.

Afterward, I swam around and marveled at the water. It's turquoise, it's milky, and it's naturally loaded with skin-softening minerals—basically, it's what I imagine is on tap in Beyoncé's bathtub.

Book a massage near you. It'll be relaxing, even without the lagoon.

3. Take the Golden Circle tour.

Tip: Do like Bear Grylls would do and wear tractioned boots.

Iceland's famous Golden Circle tour makes stops at the continental divide at Þingvellir, Gullfoss waterfall, and Geysir (a geyser). Wear your warmest layers for the first two destinations. The wind is relentless, especially at Gullfoss—and that's coming from someone who lives in the Windy City. At one point I jumped in the air, and I swear the gales carried me down the path.

Geysir is dormant, but its "little brother," Strokkur, erupts every 5–7 minutes. The steam from Strokkur and the small hot springs that surround it make for very slippery ground. I saw several people bite it, including a woman in my tour group who fell and sprained her arm. One guy took a tumble while standing still. I didn't even know that was a thing.

Take a rock-climbing or bouldering class to get more comfortable atop rocky footing.

4. Seek out Icelandic food.

Tip: If you really wanna feel adventurous, sample the "rotten shark" at Cafe Loki.

As is the case for any other vacation, getting a taste of the local food is one of the best things to do in Reykjavik and Iceland in general. During my trip, I wasn't sure what to expect from Reykjavik's culinary scene, but a Domino's next door to my hotel was not it. There are a lot of American fast-food joints in Reykjavik, and a wide range of international restaurants. Icelandic cuisine, it turns out, can be a little harder to find.

For authentic Icelandic food, go to Sægreifinn, a restaurant in Reykjavik Harbor. The owner is a former Coast Guard chef and fishmonger who created a world-renowned lobster soup sweet and buttery enough to live up to the hype. The place isn't fancy—you sit on cushioned buoys and pour your own water—but the minke-whale steak made me feel adventurous, and the arctic char was last-meal good.

Make reservations at a local seafood restaurant to get your taste buds warmed up.

5. Be a discerning souvenir shopper.

Tip: Look for the magenta Tax Free icon.

Laugavegur, one of the main drags in downtown Reykjavik, has the most merch per mile. Among the tourist shops, prices vary wildly. I saw traditional Icelandic sweaters selling for anywhere from around $110 to upwards of $185. So if you want one, shop around.

As you're shopping, keep an eye out for the magenta Tax Free icon. On qualifying purchases of more than 4,000 krónur, you can be reimbursed on the 15% tax. Simply file for your reimbursement at the airport.

Find great deals on men's and women's sweaters, scarves and wraps, and hats and gloves to combat Icelandic chilly weather.

Photos: Aurora Borealis by Moyan Brenn under CC BY 2.0 [cropped from original]; ship statue, Blue Lagoon, and Reykjavik photos by Kelly MacDowell, Groupon