This summer's heat waves made me book my first 'coolcation.' It changed what I want from a vacation.

• A record heat wave prompted Megan Carnegie to take her first-ever coolcation in Norway.
• During four days in Trondheim, temperatures of 66°F and endless daylight changed her sense of time.
• It made her rethink what makes the perfect summer getaway.

Living in London, I spend most of winter fantasizing about the sun on my skin, balmy sea swims, and the carefree mood that loosens even the most uptight urbanites.

By the time spring rolls around, I'm usually plotting an escape around maximum sunshine, beautiful beaches, excellent food — ideally somewhere along the Mediterranean, like France or Greece.

But when London hit a record 95°F in June, I surprised myself. Instead of chasing more heat, I booked a trip to Norway's third-largest city, Trondheim, for my first-ever "coolcation."

As a committed sunseeker, I was skeptical that swapping SPF 50 for a down jacket could deliver the holiday I'd made routine. Happily, what I found challenged my bias.

Swapping sunsets for the midnight sun

I'd visited Scandinavian cities like Gothenburg and Helsinki in winter, blanketed in snow and eerily dark — the version most people picture. This was my first time in the region at the height of summer. I arrived on June 17, just before the summer solstice.

I wasn't prepared for the "white nights" phenomenon. Located just south of the Arctic Circle, Trondheim never really gets dark at this time of year. On my first night, I left a candlelit basement restaurant at around 11 p.m. and emerged to blue skies and bright sunshine.

Throughout my four-day visit, I never quite adjusted. Every evening, I'd peek outside before bed, half-expecting darkness — it never came.

Norwegians make the most of every hour of summer light. With days stretching deep into the night — and fading quickly again after August — the city hums with a strange, almost nocturnal energy. Bars and restaurants stay busy late, and blackout curtains are a necessity: without them, you're at the mercy of the midnight sun.

I saw the city through a local's eyes

On most summer vacations, I come home rested, tanned, and not much wiser about the place itself. This time, though, I knew I could sightsee without the FOMO.

Trondheim, about 300 miles north of Oslo, is compact and easy to navigate on foot, so well-suited to slower exploration.

I did a walking tour with a local, stopping off at places I'd likely have missed on my own, including the Trondheim Folkebibliotek, a library built into the ruins of a 12th-century church, and the café Sellanraa. Norwegians drink the second most coffee per capita in the world, after Finland, so it felt rude not to sample its excellent coffee culture.

Even in drizzle, the painted wooden houses and warehouses flanking the waterfront held their charm. Near the Old Town, my guide pointed out the world's only bicycle escalator, a detail that felt in keeping with the city.

Trondheim also has a flourishing cultural scene, with contemporary galleries like Kunsthall Trondheim and PoMo, which had just closed a Louise Bourgeois show.

A highlight of my trip was a visit to Nidaros Cathedral, a vast Gothic structure with one of Northern Europe's largest church organs — a mere 9,600 pipes. From its deep purple stained glass to the countless saints, apostles, bishops, and Old Testament figures carved into its façade, the cathedral demanded my attention at every turn. I spotted a statue holding a basket of decapitated heads, a reminder of Trondheim's Viking history.

Feeling the heat of a traditional Norwegian sauna

Aside from a day of rain, Trondheim hovered around 66°F throughout my visit — a welcome relief after the furnace of London. The cooler air, it turned out, relaxed me. Still, I wasn't going to leave without seeking out that medicinal Scandinavian heat.

I booked a session at a self-service sauna and arrived just as a cruise ship was pulling in. Trondheim sits on Trondheimsfjorden, Norway's third-longest fjord, making it a popular stop for cruise ships.

As tourists filtered past, I settled in for a few peaceful hours, alternating between the wood-fired sauna and plunging into the bracing seawater. For a certified sun chaser, it was a perfectly portioned hit of heat.

Last year, luxury travel network Virtuoso reported that bookings for cooler European destinations surged 263% year over year. In its latest Luxe Report, the company says "staying cool remains hot," with Norway, Iceland, and Antarctica topping its list of destinations on the rise.

It felt like a special time to be in Trondheim and introduced me to new travel tenets: move slower, be more curious, and let go of "good" weather. It's a version of a summer holiday I hadn't considered before, but one I'd choose again, especially as the summers in many cities grow hotter and more unpredictable.

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