Editors' pick: Originally published June 8.
Those who have visited glaciers say the first view is a moment so stunning your breath gets caught in your throat.
The size is staggering. The colors are otherworldly. And the landscape is unlike anything else on earth.
"What you see is a landscape that is totally different then anything you've ever witnessed," says Bryan Mark, a scientist at the Byrd Polar and Climate Research Center at Ohio State University. "It's not devoid of life - there's fascinating interfaces with plants and biology. And you get this sense that you are closer to the sky. There's cloud formations you've never seen before."
The chance to witness such beauty and magnificence is just part of the reason why travelers make pilgrimages to the world's glaciers.
In some countries, such as Peru, glaciers have religious or spiritual significance and are the focus of fascinating annual cultural festivals involving tens of thousands of people worshiping Father Earth.
And many other visitors are likely inspired by the notion that it's now or never. And therein lies the controversy.
A recent Smithsonian article urged those interested in glacier viewing to hurry up and visit them before they're gone, eliminated by global warming.
It's the type of commentary that inspires complete frustration among those who believe that encouraging increased travel to glaciers will speed up their demise (due to the associated carbon emissions tied to the act of travel, among other things).
On the other end of the spectrum are those who say there is no better way to help people understand the effects of global warming, then to show them firsthand.
"In a way, it's a cop out when people say things like, 'If someone didn't go see a glacier, they would just stay home,'" says celebrated glaciochemist Sarah Aciego, who founded Big Chill Adventures. "People have a choice of where they're going to go...It's really important for people to see this themselves. The people who go, have a better understanding. Then they start asking questions and it's easier to have an intelligent scientific discussion when someone is standing right there and can see exactly what I'm talking about."
Wherever you happen to stand on this debate, the fact is that glaciers are retreating at a stunning pace. And seeing one in person is an experience unlike any other.
Here's a snapshot of what a handful of professionals and locals have to say about traveling to some of the world's most iconic remaining glaciers.
Peru is home to the largest mass of tropical glaciers in the world, and most are in the Cordillera Blanca, or White Mountains.
Glaciers in the Cordillera Blanca have decreased by 25% since 1987, according to a study published by Elsevier, which noted that overall, glacier change in the area is accelerating.
Researchers at the French Research Institute for Development (IRD) in Marseilles, meanwhile, have found that the glaciated area in the tropical Andes is now decreasing by 3% a year.
None of which is news to Rick Vecchio, a former AP reporter who covered Peru for years and who now lives in the country, working as director of development and marketing for the travel company Fertur Peru.
"Just like everywhere else, they're disappearing at a terrifying rate," says Vecchio. "Nine years ago, we watched the Nevada Pastoruri, which had been the most popular and accessible glacier for hikers, melt in a period of months into two rapidly receding patches of ice."
"This is something that is really happening, the glaciers are disappearing," he adds. "Most tour operators are not as crass as to say 'Come see glaciers before they're gone' - but they are disappearing."
And the implications of their disappearance will be devastating for Peru, a country that's home to 70% of the world's tropical glaciers, whose population is highly reliant on their runoff.
For Vecchio, who is married to a Peruvian woman and has three children, the topic is personal. What sort of life will his children inherit, he wonders?
Still, Vecchio notes, there are some wonderful hikes remaining in Peru, that get travelers right up to the ice peaks. In the Cordillera Blanca, for instance, there's Quebrada Llaca, which can be done as a day hike out of Huaraz, he says.
"I don't think there is any harm in hiking to where the glaciers are and trying to raise some awareness about them," he says.