I used an airline hack to turn a layover into a mini trip to Iceland. It was worth the short detour — and saved me money.

• I booked an airline "stopover" to visit Iceland for 4 days on my way home from Norway.
• The ticket was one itinerary and didn't cost extra airfare, but included no free hotel or tours.
• The mini-trip was expensive, despite the shoulder season, but it's an easy way to see a new country.

After five fabulous days exploring Norway's stunning fjords in mid-September, I was excited to try an airline travel hack I'd been eyeing for months: Icelandair's "stopover" program.

Icelandair allows passengers traveling between North America and Europe to stop in Iceland for up to 7 nights on a standard ticket without paying additional airfare. Higher-priced flex tickets allow up to 21 nights.

I chose a $455 one-way standard economy flight from Norway to the US with a four-day stop. All of Icelandair's transatlantic routes already pass through Keflavík International Airport near Reykjavík, making it an easy detour.

This strategy effectively added a second vacation onto my trip. I soaked in geothermal water amid moody volcanic landscapes, ate my way through Reykjavík, and explored part of the south coast.

The stopover was worth it, and I felt I had enough time to explore, but it was not a free vacation.

Iceland is expensive, even during the shoulder season, and while the airline doesn't charge extra for the stopover, it does not cover accommodations, tours, or transfers.

Still, the travel hack — which about a dozen other global airlines offer — let me visit a remote country that had been at the top of my list for years without having to book a separate trip across the Atlantic.

Booking my 4-day stopover was surprisingly simple.

Icelandair's booking engine has a dedicated stopover option. I entered Bergen, Norway, as my origin and Portland, Oregon, as my final destination, chose the dates I wanted to arrive and depart Iceland, and booked both flights on a single itinerary.

I stopped in Iceland on my way home from Norway because the logistics and airfare worked out better than they had on my outbound trip. Flight prices can vary widely by day of the week, so it's worth comparing a few departure dates before booking.

The flight from Bergen to Iceland was two and a half hours, and the flight from Iceland to Oregon was about eight hours. Icelandair's economy service was very basic and felt sparse for an international flight. Water, coffee, and tea were complimentary, though meals and snacks cost extra.

Saga Premium, the airline's highest-tier cabin, was a marked step up, with a wider recliner seat, more legroom, meals, WiFi, and complimentary drinks. It looked far more comfortable but came with a significant price jump — up to $2,000 or more one-way, depending on the date.

Four days gave me time to see more of the country.

Booking a few days in Iceland proved to be key to enjoying the stopover. Staying only one night would probably be more effort than it is worth.

Keflavík Airport is roughly a 45-minute drive from Reykjavík, so an overnight stop might amount to one of Iceland's iconic lagoon soaks, then dinner, sleep, and another trip down the same highway.

Two or three nights is ideal if you want to get a feel for Reykjavík. And the freshly baked cinnamon rolls at Brauð & Co are arguably reason enough to add a few-day stopover.

I found that staying for four or more days let me split my trip, spending a few days in Reykjavík and a few days exploring deeper into the desolate, elemental country.

The stopover does not include a hotel or activity discounts.

Icelandair does not include a stopover hotel, and passengers must arrange that separately, but they are eligible to book tours and transfers through the airline.

Some other airline stopover programs do offer passengers free overnight accommodations.

For example, Turkish Airlines stopover passengers can select from specific comped hotels, Etihad Airways offers eligible travelers up to two complimentary nights in Abu Dhabi or Al Ain, and Qatar Airways sells Doha stopover packages, including hotel stays starting at $14 per person.

However, the stopover hotels are sometimes far from the city's main attractions, and passengers are often better off booking on their own based on what they want to do.

I found that not having a set hotel gave me the freedom to explore.

I spent two nights at The Reykjavík EDITION, a 5-star luxury hotel, for around $800 a night. My room had harbor views and put me within easy reach of the city's main attractions. Reykjavík also offers more affordable hotels, guesthouses, and hostels for budget travelers.

I also stayed a few nights on the south coast, where people can do more adventurous activities.

You will need a plan to get beyond Reykjavík.

Iceland looks compact on a map, but its best-known sights are scattered hours from the capital city, and there are no passenger trains.

Bus service reaches many towns, but travelers who want to efficiently reach sights beyond Reykjavík will likely want to rent a car, hire a driver, or join a tour.

We drove down to the south coast to see beyond the city life. We stayed at a boutique hotel called Hotel Rangá, near Hella, about 60 miles from Reykjavík. It was around $650 a night, but we had plenty of hot tubs and direct access to some of Iceland's best outdoor adventures.

While we pieced together our own trip, passengers can also book excursions, like horseback riding, whale-watching, lava tunnel adventures, and a Golden Circle and lagoon day, through Icelandair.

However, booking through the airline doesn't necessarily mean getting a discount, so it's worth comparing prices with individual tour operators before reserving.

More active travelers can join guided glacier hikes or ice-cave tours, or bounce across black sand in a buggy.

For me, the stopover was worth it

Michael Raucheisen, Icelandair's North American communications manager, told me the airline formally began promoting stopovers in the 1960s.

The point was not simply to make connections less tedious, but to expose travelers to Iceland and encourage them to return: "That's kind of the goal, to give you a small little taste to make you want to come back," Raucheisen said.

It worked on me.

Iceland is unlike any of the dozens of other countries I've visited, from its moody volcanic vistas and geothermal activity to its down-to-earth people, world-class hot dogs, and the country's nose-wrinkling national drink, Brennivín.

But Iceland is not a cheap country to visit. While traveling with another person helped us split the hotel costs, I estimate my share of our four-day trip was about $510 per day, or roughly $2,050 total, excluding airfare.

That includes hotel nights and typical daily costs for food, sightseeing, and local transportation. Travelers could likely lower that cost by choosing less expensive lodging.

Still, though I may not do it as expensively every time, I look forward to adding a few nights in Iceland whenever the route and fare make sense — it's a chance to see more of the country without paying for a whole separate trip.