(CNN) — Summer travel can be so inviting. There are fewer clothes to pack. Days are long for outdoor adventures. Al fresco dining abounds. And you can't overstate the simple joy of basking in the sun's soothing rays.
But sometimes you can get way too much of a good thing in summer as people in the Western United States can tell you. Too much heat is not just unpleasant. It's deadly.
Whether you're playing it safe or simply prefer relatively cooler temps over hot spots, here are nine places that usually make for cool travel escapes in summer. Keep in mind all the cautionary guidance about travel -- especially if you're not fully vaccinated or you're crossing international borders.
Mountainous Switzerland always provides a cool spot somwhere. Dent Blanche, left, is next to the Matterhorn in the Swiss Alps.
Fabrice Coffrini/AFP/Getty Images
Should the major cities such as Geneva, Zurich and Bern become too hot for you (which is unlikely, especially at night), escape to the higher altitudes for an Alpine hike. Even in mid-July, temperatures on the 5 Lakes Walk near the Matterhorn can stay on the cool side. If you want something less strenuous, take a boat tour of idyllic Lake Brienz.
2. San Francisco
Alcatraz Island can be seen from the Russian Hill neighborhood in San Francisco.
Brontë Wittpenn/The San Francisco Chronicle/Getty Images
"The coldest winter I ever spent was a summer in San Francisco."
The quote oft-attributed to Mark Twain is nice summation of the weather there. Summer isn't even its warmest season -- that honor goes to fall. While much of the Northwest has been baking this year, the city's microclimate has kept things cool.
You can explore neighborhoods such as hilly Russian Hill (home to crazy crooked Lombard Street) or head out to nearby Muir Woods for some serious tree time. Don't forget a light jacket.
3 . Anchorage, Alaska
A cool sight: Spencer Glacier in Chugach National Forest.
Alaska isn't necessarily the year-round ice block you may think it is. It can get surprisingly warm at times in Anchorage. But compared with the Lower 48, it's still usually a relatively cool escape in summer. (In mid-July, CNN Weather forecasts the hottest day to be 76 F (24 C).
Seljalandsfoss waterfall is a spectular sight in southern Iceland.
Sven-Erik Arndt/Arterra/Universal Images Group/Getty Images
With a name like Iceland, you'd better be cool -- unless you're near a lava flow or soaking in a hot spring. Average July highs in the capital of Reykjavík are 14 C (57 F).
A skier competes during DXB Snow Week at Ski Dubai last year.
Francois Nel/Getty Images
No, we haven't lost our minds. Dubai is indeed a hot desert emirate. But it offers year-round snow skiing and other winter activities. How can that be?
It's all thanks to Ski Dubai. When you're rolling in oil money, you can build a mammoth indoor ski park and draw folks from all over the world. Along with the skiing, you can have penguin encounters, ride snow slides or take a chair lift for a bird's-eye view.
6. Air-conditioned destination malls
You can retreat to destination malls such as CentralWorld in Bangkok and spend a full day indoors and never get bored.
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Online shopping has delivered a big blow to many malls, but there are big destination malls in the USA and around the world that can still satiate your shopping and entertainment appetites in glorious, air-conditioned comfort.
Minnesota's Mall of America is a kids' climate-controlled playground paradise with everything from an aquarium to the Nickelodeon theme park. Even hot, steamy Bangkok offers a cool respite if you go to malls such as CentralWorld, where there's an ice skating rink.
Stay aware of any local mask-wearing requirements when you visit enclosed public locations. Even if you're fully vaccinated, some locations still might ask you to wear a face mask.
7. Caves for tourists
You can see stalagmites, stalactites and formations called curtains in the Postojna Caves.
Jure Makovec/AFP/Getty Images
-- Mammoth Cave National Park, Kentucky: The longest known cave system in the world has an average temperature of 54 F (12 C). Bring a jacket for your tour. -- Eisriesenwelt Cave, Austria: You go from cool to downright cold here. This is an ice cave and one of Salzburg's favorite things. -- Postojna Caves, Slovenia: See stunning formations from the comfort of an underground train.
8. Fresh-water swimming holes
An old stone bridge spans the Voidomatis River.
There are all kinds of fresh-water swimming holes around the world that provide an exhilarating plunge even when it's insufferable hot on land. A couple of examples:
-- Barton Springs; Austin, Texas: Residents and visitors can escape the notoriously brutal Texas heat in this naturally fed pool, where the water is always 68 to 70 F (20 to 21 C). On a cold winter morning, the pool actually provides a relatively warm place to swim. -- Voidomatis Springs, Vikos Gorge, Greece: These spring-fed pools can be found on the Voidomatis River, deep in the Vikos Gorge in northern Greece. Be aware they can run dry in late summer.
9. Cold-water beaches
A couple walks the shore at Coast Guard Beach in Eastham on Cape Cod.
Craig F. Walker/The Boston Globe/Getty Images
Even if the sun is out in force, some beaches have cool water ocean currents that make for chill air and bracing -- even shocking -- dips. A few of them are:
-- Nazaré, Portugal: This charming spot on the Portuguese coast north of Lisbon is known for surfing, but the waves are generally biggest in winter. The Atlantic is usually calmer here in summer. The water temperature in mid-July was 16 C (61 F). -- Bryher; Isles of Scilly, UK: Bryher has rough Atlantic waves on one side, but calm, sandy beaches on the other. It's about 40 kilometers (25 miles) off the southwestern tip of Cornwall. The water is pretty cold for long swims unless you're very hardy, but it doesn't take long to cool off with a dip here.