I'm often asked: "What is your favorite country to visit?"

For an avid adventurer, it's a confounding question. How to distill culture, vibes, food, scenery, and all the other factors that shape the international travel experience?

Identifying the nations I have explored in depth over multiple visits — popular places like Turkey, Nepal, South Africa and Indonesia — is one measure.  A more novel approach might be to consider the places I expected to visit only once but which surprisingly left me wanting more.

Here are the spots I thought would be "one and done" but that are on my list of return trips.

Rwanda

I was unprepared for the natural beauty of Rwanda. Like many, I traveled to Rwanda for the primate trekking. But the sudden closure of the Burundi border meant I had some extra time.

What a serendipitous gift it was to discover gorgeous tea plantations, a luscious landscape of a thousand hills, and the singing fishermen of Lake Kivu who work at night from tri-hulled boats. 

Rwanda gets kudos for its reconciliation after the 1994 genocide. Across the country there are genocide memorials, which approach its difficult history respectfully and transparently.

The primate trekking is not too shabby, either. I ventured to Volcanoes National Park in search of the golden monkey, a photogenic sub-species found in central Africa's Virunga Mountains. I was hoping for a close-up, but instead got a close encounter. One mischievous monkey found his happy place between my feet.

Saudi Arabia

At a dramatic cliff named the "Edge of the World," I watched the amber sun drift below the horizon on my first day in the Kingdom. The vast, uninterrupted views will be hard to top, I thought.

A few days later I experienced another Saudi superlative while immersed in a fertile green valley surrounded by massive red sandstone pillars. I wandered Wadi Al Disah, or "Valley of the Palm Trees," in disbelief that a desert environment could be so sublime.

Wadi Al Disah is the geological cousin of Jordan's Wadi Rum — but without the crowds. The Nabateans built the now world-famous site of Petra 2,000 years ago. They also built Hegra, a prized World Heritage Site in Saudia Arabia, which is most interesting after dark.

In the evening, a section of its monumental tombs is illuminated by thousands of candles, creating the mystique of an ancient civilization. Mass tourism is relatively new in the Kingdom, and I felt genuinely welcome, thanks to the Arabian hospitality. The highlight of my journey: a spontaneous offer to visit a Bedouin camp. Our hosts invited us inside their tent compound and shared tea, photos and stories of their nomadic lifestyle.     

Montenegro

Some years ago, I cycled through this small gem of a country and its mountains, turquoise waters and Orthodox churches. While nearby Croatia gets most of the attention and visitors, Montenegro is the place to wallow in Adriatic ambience.

The UNESCO-honored Bay of Kotor is often called Europe's southernmost fjord, but it's actually a submerged river canyon.

Near the Stari Grad (Old Town) of Kotor, I hiked up to a fortress and popped into a Serbian Orthodox church that dates to 1305. Inside I found a talkative priest. Somehow, he and I overcame the language barrier to have a good chat.

Cycling along the Adriatic Sea toward Albania, I spotted the peninsular village of Sveti Stefan. I was just passing through. But the lingering image of that rustic hamlet with red clay rooves, fringed by blue shades of sea, calls me back.

Antarctica

On my journey "Way Down Under" I was among the very first visitors of the season, which begins in mid-November. 

In Antarctica the colors are pure and spectacular: endless, unblemished whites punctuated by fiery orange sunsets. The pristine places we explored on foot and by kayak had been untouched for at least six months during the brutal winter.

On King George Island, a crew member of our expedition ship reached out to the nearby Polish research base, staffed by just seven members. After a long winter, the researchers were beyond eager for some fresh faces. They invited us into their intimate living quarters, generously sharing chocolates, snacks and precious fruit. I am eager to return to the White Continent again to experience the planet's coldest, windiest, driest, and perhaps most serene place.

Vanuatu

Vanuatu is one of the least visited countries in the world, not because it isn't welcoming or rewarding, but because of its remoteness. The voluntary liquidation of its national airline, Air Vanuatu, in May doesn't help.

Still, this Melanesian country offers breath-taking experiences — including the world's most accessible active volcano, Mount Yasur, known for its natural fireworks of agitated lava. I was engulfed in thick toxic volcanic smog with near zero visibility during my visit to the rim.

The archipelago's clear waters and coral reefs are world class. Off the coast of Efate island, I snorkeled over a downed but intact World War II Corsair fighter plane; the pilot reportedly survived the crash.

Vanuatu also oozes tribal tradition. On Pentecost Island we witnessed a land-diving ritual, the original bungee jumping. During this annual rite of passage, men take a leap of faith from high wooden towers with banyan tree vines wrapped around their ankles. In the background, men wearing penis sheaths and women in grass skirts ceremonially sing and dance. They say a good dive ensures a bountiful yam crop. That day we witnessed 10 successful dives, which should bode well for the harvest.