Episode 4: Unraveling a mapmaker’s dangerous decision

For much of recorded history, maps have helped us define where we live and who we are. National Geographic writer Freddie Wilkinson shows us how one small line on a map led to a bitter conflict in another country, thousands of miles away.

Two soldiers, just back from 30 days at Conway Saddle, Pakistans highest held ground in the Siachen conflict with India at above 20,000 ft. sit for a portrait back down at the 16,000 ft Concordia Admin Post. Soldiers serving among some of the world’s most colossal mountains rely solely on each other during rotations. Morale goes up and down in the harsh conditions. Should emergencies arise, medical help is a long way off.
Photograph by Cory Richards

For much of recorded history, maps have helped us define where we live and who we are. National Geographic writer Freddie Wilkinson shows us how one small line on a map led to a bitter conflict in another country, thousands of miles away.


ABDUL RAHMAN BILAL (PAKISTANI VETERAN): So I told them that they didn't have a chance. And for the sake of their wives and children, they should vacate the area and go back. Both of them, they sunk [out of sight]. At that time I heard the cocking of weapons. Once both of them cocked their weapons, I knew they meant business.

PETER GWIN (HOST): This is Brigadier Abdul Rahman Bilal, a retired Pakistani army officer. His son helped him set up a Skype call with me from his home in Rawalpindi, where I could hear small children and the Muslim call to prayer in the background. He’s wearing a traditional wool pakol cap, a thick parka, and spoke through a long grey beard about events in 1989 that have made him famous in Pakistan.

BILAL: I was nominated to personally lead this operation of assault on the enemy position and to dislodge him from height 22,158.

GWIN: Height 22,158. In just about any other part of the world, this peak would be a major tourist destination, a place ambitious climbers would flock to. It’s taller than the tallest mountains in North America, Africa, Europe, and Antarctica. But in the Karakoram, home to some of the world’s most colossal mountains, no one has bothered to even name it, or dozens of other similar peaks around it. It’s referred to on maps only by its height in feet. Nevertheless, it holds a significant if macabre distinction.

BILAL: Never in the history of mankind has there been ground combat at the altitude of 21,158 feet. So this is a record.

GWIN: Four miles above sea level is not an ideal place to fight a battle. Mountaineers know this altitude can be deadly because of the low level of oxygen and the subfreezing temperatures. And then there’s the matter of getting up there. The air is so thin that helicopters can stall if they get too high. And Peak 22,158 was covered in heavy layers of unstable snow. Four men had already died in an avalanche, attempting to reach it on foot. So Bilal explained that his forces had to be carried up one by one on ropes dangling beneath the struggling helicopters.

BILAL: This is called a sling load operation. We lifted people one at a time. Such an operation has never been planned in the history of mankind before.

GWIN: And this whole thing started in part because of an error on a map: A tiny line in this remote mountain wilderness pushed two powerful nations to fight on the highest battlefield on Earth. And no one knew where the line came from, until now.

I’m Peter Gwin, editor at large at National Geographic magazine, and you’re listening to Overheard, a show where we eavesdrop on the wild conversations we have at Nat Geo and follow them to the edges of our big, weird, beautiful world. This week we look at the imaginary lines we draw to divide up the world. As we’ll see, those lines aren’t always easy to draw. And the consequences of a tiny mistake could be deadly.

More after this.

GWIN: There is a nearly 40-mile-long imaginary line that sits high in the Karakoram Mountains, far away from civilization. The line is—or at least it was—a boundary between India and Pakistan. And it cuts right across one of the planet's longest glaciers, the Siachen. This ancient glacier is essentially a frozen river that for millennia has been winding its way between mountain peaks and flowing downhill inch by inch.

MARTIN GAMACHE (GEOGRAPHER, NATIONAL GEOGRAPHIC): It's like a big ice snake. I mean, I always think of it as a snake because it's got all these ripples and all the crevasses, and it kind of looks like almost like a backbone or something. You know, if you imagine a snake skeleton, it almost looks like that.

GWIN: Martin Gamache is the director of cartography at National Geographic magazine. He and the other geographers here in the office have spent a lot of time looking at satellite images of the Siachen Glacier, but not just because it’s pretty. In that sprawling expanse of white, they were searching for something.

GAMACHE: And then if you're an astute observer, what you're going to see is, you'll see like little roadsthat— the human footprint in that area. But from—you know, if you're zoomed out, you don't see a lot of that. The human presence in this area is still very, very low.

GWIN: As you might imagine, a glacier is not an easy place to travel. And before satellite images, it was largely unmapped. Martin says that just a few years ago, state-of-the-art maps of this area were blank, unknown territory, the modern equivalent of the medieval “there be dragons.”

GAMACHE: In this part of the world that we're talking about, even up until fairly recently, those base maps still had huge holes in them. They didn't even always understand the terrain.

GWIN: I mean, that's stunning to think. But you’re telling me that as recently as 1999 you were working with maps that had still had blank spaces.

GAMACHE: Yeah. And that, to me, is the essence of why this is an exciting job, because everybody will say, Oh, everything's been mapped, right? It's like, well, yeah, but to what level of detail? And what does that mean to be mapped, you know? Yeah, we know that there's a mountain there, but no, we don't actually know how high it is and we don't know how it relates to these other mountains necessarily.

GWIN: This is going to really show my map ineptitude potentially, but I've got a family atlas I'm going to grab off the shelf here, if I can actually find it.

GWIN: OK, I wouldn’t exactly call myself a hoarder, but things have piled up in my study over the years. A Tuareg sword, a rock I found in the Himalayas that kind of looks like a snow leopard, a box of fungus from China that’s said to help you live longer—I’ve never thrown that away. And somewhere in the middle of all this, is an old National Geographic atlas.

GWIN: I can see Kashmir. But where is Hodgson's line? Where would I find it on a map like this?

GAMACHE: Well, the thing about Hodgson’s line is it's literally like a straight line. You—if it's on there, you can't miss it.

GWIN: And, oh, I see it. I see it right here. I think actually—you know, if I’m looking at this, it's like half an inch long, you know, like basically the size of maybe two ants.

GAMACHE: That’s Hodgson's line. Yeah. It kind of makes a triangle there in that furthest northern part of India.

Martin is one of the first people in the world to call this boundary “Hodgson’s line.” That’s because before our team started researching the story, no one knew where the line came from.

FREDDIE WILKINSON (WRITER, NATIONAL GEOGRAPHIC): It's amazing that you could have such a seemingly inconsequential mistake that can in part lead, you know, countries to war. And there are still thousands of soldiers who are up there bearing witness to this issue.

GWIN: This is Freddie Wilkinson, the writer who worked with Martin to track down the mystery of this line. But before you can understand how this line led to combat, you need to know a little context about India and Pakistan.

WILKINSON: The seeds for the Siachen dispute were sown at the very birth of Pakistan and India. After World War II, the British Empire was collapsing economically, and the British made the decision to get out of South Asia as quickly as possible.

GWIN: Before World War II, Pakistan and India were both part of the same British colony.

WILKINSON: They decided very early on on a two-state solution where there would be a India for the Hindu majority and a Pakistan for the Muslim people.

GWIN: In 1947, the British left South Asia.

WILKINSON: And within weeks of that independence, Pakistan and India were fighting over Kashmir.

GWIN: Violence broke out across the new border as the population reshuffled.

Muslims tried to get into Pakistan and Hindus tried to get into India. As many as two million people died in the chaos. Things were especially complicated in the region of Kashmir. That’s because India and Pakistan both believed—and still believe—that it should be part of their respective nations.

WILKINSON: When the dust settles from this initial war between India and Pakistan, Kashmir is divided.

GWIN: Representatives from the two new countries and the United Nations drew up a ceasefire agreement. Part of that agreement was a boundary that wound through Kashmir, and surveyors were dispatched to draw this line.

WILKINSON: But a curious thing happens. After defining this line all the way through Kashmir, the survey team stopped about 40 miles before the Chinese border. Rather than actually finish their job, at a certain coordinate point they inserted this language that said the border was to run, “thence north to the glaciers.”

GWIN: It was a vague phrase—especially for something as sensitive as a national boundary line. But at the time, it was impractical to be more specific.

WILKINSON: For the survey team to actually succeed would have required elite mountaineers of that era to be guiding them. So it makes sense that they would have looked at this terrain and figured, let's wrap it up and go home.

GWIN: Yeah.

WILKINSON: It must have seemed to them back in 1949 absurd that anybody would bother fighting over this territory.

GWIN: So the boundary stopped in a dead end, just short of completely dividing the two new countries. According to the UN treaty, maps of the region should show a gap, roughly 40 miles, in the official dividing line between Pakistan and India. That’s a rare oddity for geopolitical maps, but an important one. And then quietly and inexplicably, in the 1970s maps began to appear all over the world, showing the border completely connected. On a map like my home atlas, this tiny line was hard to notice. It’s something of a geographic needle in a haystack. And It took more than a decade for someone to come along with the right combination of knowledge about history, politics, and mountaineering to notice that the line didn’t belong. To understand how the line was discovered, I spoke with Indian journalist Nitin Gokhale.

GWIN: So maybe you could tell me a little bit about how that line was discovered, at least by the Indian side.

GOKHALE: In 1978 a very famous military mountaineer, Colonel “Bull” Kumar—Narendra “Bull” Kumar—was seconded to accompany a German rafting expedition on the Indus River.

GWIN: As a military officer and an avid climber, Bull Kumar had a lot of experience in the mountains and knew the maps of the region by heart. He’d been asked to assist a pair of German adventurers who were planning an expedition in the region.

GOKHALE: So after spending a couple of months with them, he saw some very fancy new maps that they were carrying. They were the U.S. maps.

GWIN: That’s when he saw the line that closed the gap in the border. And he knew it shouldn’t have been there.

GOKHALE: And he being a mountaineer, he being a military man, he got alarmed, and he went straight to the Indian military, the army chief, in Delhi, and so they came there, and they discovered that, yes, the Pakistanis were coming in.

GWIN: Meanwhile Pakistan had been treating the new line as fact, and had been sending expeditions to the area. Things slowly escalated between the two countries.

GOKHALE: The intelligence reports in December of ‘82 onwards kept suggesting that Pakistan is planning some kind of expedition or some kind of deployment on the Siachen Glacier.

GWIN: India sent troops to occupy the area in 1984 and quickly took several peaks. That gave them control over a huge swath of the Siachen. Pakistan sent troops to push them back. The fighting was brutal. The men struggled to breathe in the thin air, while trying to avoid avalanches and frostbite, all while shooting at each other. And that brings us back to Bilal, the Pakistani army officer yelling at two Indian sentries atop Peak 22,158.

BILAL: And I repeated once again that they should go back. If they vacate the area, there's nothing between me and them. I don't want bloodshed. Then there was a yell, both of them emerged, and they fired at me.

GWIN: The two groups exchanged shots. People on both sides were killed, but Bilal had the advantage. He had attacked during a blizzard and caught the Indian outpost off-guard.

BILAL:  At somewhere around 9:15 in the night, they said that one officer and three of the soldiers had died. So they cut the ropes themselves. They burnt their tents and they withdrew at nighttime. There was a big— a lot of cheering from the people on the other side in the rear. And we knew that we'd won. 

GWIN: The Pakistani army succeeded in taking Peak 22,158. But the Indians held on to many others. And over the next 30 years, the two forces struggled for control of the strategic peaks around the Siachen. And after years of fighting, a ceasefire has taken hold. Thousands of soldiers have died over this remote piece of mountain and glacier. Most of those deaths have nothing to do with combat and are related to the extreme altitude and environment: hidden crevasses, avalanches, pulmonary edemas. And they were at least partially caused by this mysterious line on a map. But no one knew where the line came from. Our writer Freddie Wilkison spent more than six years investigating. He researched archives, traveled to India and Pakistan, and visited the U.S. State department where he met with an official named Dave Linthicum.

WILKINSON: It's a nondescript office suite in a government building—you have to go through a metal detector and security to get in, and Dave ushered us into his room where he works at a cubicle. And taped above his desk is a photo of a man, Robert Hodgson.

DAVE LINTHICUM (RETIRED BOUNDARY ANALYST): I posted that right where I could see it all the time to remind myself, not eff up like he did.

GWIN: This is the man who kept a black-and-white photograph of Robert Hodgson above his desk.

LINTHICUM: Dave Linthicum, boundary analyst, retired, U.S. State Department, Office of the Geographer.

GWIN: Dave has retired from the Office of the Geographer since meeting with Freddie. And he spoke with us on the condition that we say, "Dave's comments do not necessarily represent those of the U.S. State Department." Dave is like the Alex Trebek of geography.

GWIN:  What is the- what is the Office of the Geographer?

LINTHICUM: Since 1953, it's had the authority… (audio continues under narration) ... to provide advice and do research on and has, along with the policy bureaus of State, done international boundary depiction and set U.S. government policy in terms of international boundary portrayal. 

GWIN: The kind of person where you could spin a globe, put your finger on a random point, and he could probably give you a precise, articulate analysis of its geography, history, and salient political issues. In short, Dave is just the kind of person you’d want as a boundary analyst for the Office of the Geographer. That office figures out exactly where U.S. government policy says the boundaries between countries should be. For example, the line between India and Pakistan. In the summer of 1968, the Office of the Geographer received a message from the U.S. embassy in New Delhi. They asked how the U.S. should regard several border disputes India had with its neighbors, including Pakistan. The request fell to—you guessed it—Robert Hodgson, who was an assistant geographer in the office. After a few months, Hodgson responded with a memo that stated: Going forward U.S. maps would show a completed boundary through Kashmir, closing the 40-mile gap.

LINTHICUM: Rather than follow the 1949 ceasefire agreement text, which says “thence north to the glaciers,” instead Hodgson drew a line that was a whole lot more east the north, favoring Pakistan.

GWIN: Hodgson had closed the gap in the border, making the new line official on U.S. maps. But he also tried to keep it quiet.

LINTHICUM: Hodgson authored a memo where he said that this present memo is being used rather than our usual outlet to keep publicity to a minimum in changing the depiction of the boundary between India and Pakistan. That bit about keeping the publicity to a minimum didn't work.

GWIN: The U.S. government publishes thousands of maps every year. And commercial map publishers, including National Geographic, often took their cues from those government maps. So this tiny line spread throughout the world. And  it was just a matter of time before it sparked this conflict. So why did Hodgson do it? The  answer is, well we don’t know. First, we should note that Robert Hodgson died in 1979. So he didn’t live to see the consequences of his line. I’ve been Freddie’s editor on this, and I’ve watched as he and Martin have researched this story for six years, and that whole time, Robert Hodgson was like a ghost to us. We wanted to get a full picture of who he was, but many people who knew him had died. Freddie finally tracked down one of his former colleagues and two of his daughters. They filled in some of the details. For example, he was a funny dad, who took the bus every day to work. He earned a Purple Heart as WWII marine and was well known for his straight-shooting personality and his precision in marking borders all over the globe. He was so well respected as a geographer that an underwater mountain in the Atlantic was named in his honor. We don’t know for sure, but based on everything we’ve learned about his life, it seems that this line was simply a mistake.

LINTHICUM: And it's just testament to if you do a thousand things right, you make one thing wrong—you might be known for the one thing.

GWIN: Dave probably understands how Hodgson might have felt better than anyone because, in addition to being one of his successors in the Office of the Geographer, Dave also started a conflict with a misplaced border.

LINTHICUM: Well thanks, Peter, for bringing up my biggest mistake. I appreciate that.

GWIN: In 2010, Nicaragua sent 50 troops into a small sliver of Costa Rica.

They claimed the area was part of Nicaragua because that’s how it was labeled on Google Maps. Costa Rica responded by sending in troops of their own, and the two groups had a standoff in what has been called the first Google Maps war. And Dave’s boss at the State Department found out the next day.

LINTHICUM:  He said, you know, they're blaming this invasion of Costa Rica by Nicaragua on Google Maps—didn't you draw that line, Dave? And I said, Yeah. And I knew the next few weeks were going to be a bit tough. I drew the line incorrectly—just for the last couple kilometers, but that’s all it takes.

GWIN: Dave had made a small mistake. Google worked quickly with the State Department to correct the border, and luckily no one was hurt. Drawing borders is tricky because they mean a lot to the people who live there. And it’s something our own geographers face here at National Geographic, even with all the benefits of modern satellite imagery. As Martin’s team was making a map for this story, they had the same problem Hodgson had: Where do you draw the line?

GAMACHE: As we were reporting our story, one of the things that we tried to do is look at a lot of satellite imagery—really detailed satellite imagery—and map where Indian positions and Pakistani positions were on the glacier. And at a certain point, like, you start going cross-eyed and thinking every little rock on the glaciers is an Indian, you know, antiaircraft or artillery position, and, you know, you kind of have to back up and say, OK, well, is this a speck of dust or is it something real? And then, you know, also like, oh, there's all these Indian positions here in Pakistan that nobody really like described before. They're clearly like on the other side of the boundary. Does that mean we should redraw our line? So now we're faced with the dilemma of do we do what Hodgson did and kind of redraw the line? Do we change what is an agreed-upon line of control between India and Pakistan to reflect what is actually happening on the ground, which both sides have—are operating on each other's territory? Do we make that statement on our map, or do we wait and let somebody else decide when to do that?

GWIN: I think one of the things about this story that hits me sort of in the gut every time I stop and think about it is, you know, these imaginary lines— it's a very academic sort of drawing room exercise until those lines turn into actions that lead to things like people being killed in this mountain range. Do you ever think about that? I don’t think I’m doing a good job of describing it.

GAMACHE: Yeah, I think about that all the time. You know, you never know fully what the consequences of your actions are going to be until you've triggered it. So I don't think Hodgson expected to—you know, if he was to see or if he saw the outcome of this, I don't think he thought, Oh, India and Pakistan are going to be fighting a 30-year war on top of the world and people will die. I don't think he anticipated that at all. But once it happened, everybody said, Oh, well, you know, he should have known, of course.

GWIN: OK, so let me ask you this. This [atlas] is 2016. So do we still show Hodgson's line now like this?

GAMACHE: No, no we don't. We don't. We removed Hodgson's line and replaced it with a claim line by Pakistan to all of Jammu and Kashmir. We give them each equal treatment.

GWIN: To this day, the area where Hodgson’s line used to be is occupied by Indian and Pakistani military forces. The official line no longer exists, but its shadow lingers. On the highest battlefield on Earth, the theoretical line has been replaced by a very real line of opposing militaries.

More after this.

GWIN: The Himalayas are home to all kinds of unusual geography. The most famous, of course, is the tallest mountain in the world: Mount Everest. But exactly how tall is it? A team from Nepal and China recently remeasured it and came up with a new official height. You can read about the science behind it in our show notes.

You can also read about a team of 10 Nepalis who completed the first winter ascent of K2, the world’s second tallest mountain, which isn’t far from the peak Bilal’s men attacked.

Like many international conflicts, the history of Kashmir is complicated. Luckily our culture team has put together an article explaining the history of the princely state of Jammu and Kashmir that helped me understand the basics of the conflict.

And subscribers to the magazine can read Freddie’s article, which includes more details about Robert Hodgson’s life and the consequences of his line. And you can also explore Martin’s detailed maps of the Siachen.

That’s all in the show notes, right there in your podcast app.


Overheard at National Geographic is produced by Brian Gutierrez, Jacob Pinter, Laura Sim, Carla Wills, and Ilana Strauss.

Our senior editor is Eli Chen.

Our executive producer of audio is Davar Ardalan.

Our fact-checker for this episode was Brad Scriber.

Our copy editor is Amy Kolczak.

Hansdale Hsu sound-designed this episode and composed our theme music.

Special thanks to members of Robert Hodgson’s family: His daughters Amy Wilcox, Sue Somerfeld, and Laura Johansen, who generously shared memories of their father.

This podcast is a production of National Geographic Partners.

Whitney Johnson is the director of visuals and immersive experiences.

Susan Goldberg is National Geographic’s editorial director.

And I’m your host, Peter Gwin. Thanks for listening, and see y’all next time.


For much of recorded history, maps have helped us define where we live and who we are. National Geographic writer Freddie Wilkinson shows us how one small line on a map led to a bitter conflict in another country, thousands of miles away.

For more information on this episode, visit nationalgeographic.com/overheard.

Want more?

Everyone knows Mt. Everest is the tallest mountain in the world, but exactly how tall is it? The science and politics behind finding that number is surprisingly complicated. A team from Nepal and China recently came up with a new official height.

The world's second tallest mountain, K2, is only a few miles away from Hodgson's line and the Siachen glacier. Just a few months ago a team of 10 Nepalis completed the first winter climb of the mountain.

The history of the Kashmir conflict is complicated. Here's a straightforward explainer of how it all started.

Also explore:

Magazine subscribers can read Freddie Wilkinson’s full article, including more details about Robert Hodgson’s life and our geography team's detailed maps of the Siachen glacier.