“Der be somtin’ in me boot, man,” shouted Troy Henry in Caribbean-English creole—his primary tongue as a native Guyanan. “It gone bit me!”

Troy had just arrived on Tarantula Terrace, a vegetated ledge the size of a dinner table, three rope lengths up the northern prow of Mt. Roraima. He was wearing Waldo Etherington’s jungle boots—two sizes too big for him—as he didn’t want to ascend the huge, overhanging wall in his gumboots.

The mythical Roraima—which inspired Sir Arthur Conan Doyle’s classic work of fiction The Lost World and provided the setting for the animated film Up!—is a huge, flat-top “tepui” on the tri-point border of Guyana, Venezuela, and Brazil. In 1973, a large Anglo-Guyanese expedition—led by Hamish MacInnes with an all-star team consisting of Joe Brown, Don Whillans, and Mo Anthoine—traveled overland through Guyana and made the first ascent of the Great Prow, relying heavily on aid climbing techniques and a small army of Amer-Indian porters. I’d seen the expedition film as a young climber, and it painted a picture of great suffering and misery but also swashbuckling adventure. Perversely, it inspired me to organize my own expedition to Roraima three decades later.

While the entire mountain is stunning, the Great Prow is without comparison. It rises above the lowland rainforest like the bow of a gigantic ship for almost 2,500m, half of which is precipitously steep, with the final 450m consisting of overhanging bulletproof quartzite estimated to be some two billion years old. The area below the cliff is an astoundingly wet and humid place, home to bizarre botanical and zoological wonders, including bird-eating spiders and scorpions whose sting can induce vomiting of blood.

The extremely remote Akawaio community of Phillipai in Guyana has the nearest air strip to the Great Prow. It is only 40km to the east as the crow flies, but the dense rainforest and the arc of the terrain result in an approach trek of precisely 100km. Wilson Cutbirth, Waldo Etherington, Dan Howard, Matt Pycroft, Anna Taylor, and I arrived in Guyana in early November and set in motion a plan to deliver supplies to the mountain for our attempt on an all-free line somewhere on the Great Prow.

On November 8, we chartered a skytruck—an aircraft like a Mercedes Sprinter with wings and a large tailgate door—and flew from the capital,Georgetown, for around two hours. On reaching the mountain, we threw out four 125kg parachute loads into the trees below. Our self-designed aerial delivery system suspended the loads 60m below the parachutes, allowing them to penetrate the forest canopy and reach the ground before the parachutes inevitably became entangled high in the trees. A homemade locating device, featuring GPS, radio, strobe, and 120-decibel beeper, was attached to our mission-critical loads.

The seven-day trek through the jungle was far more pleasant than anticipated, and eventually we located the loads, retrieved the parachutes, and began the climb. But first we had to get to the prow itself, which meant ascending a slime forest of fantastically contorted, stunted trees and dangling icicles of transparent ooze. We emerged into the “Eldorado Swamp,” an open area that looked like a decent campsite before we realized it consisted of ankle- to knee-deep white mud. In another intense downpour, we pushed through. Then came a garden of enormous tank bromeliads, capable of holding hundreds of liters of water, which could either be navigated by balancing on top of them or tunneling under, occasionally drenching one of us when the tank toppled. A final section of vertical, bamboo-like undergrowth, through which I more burrowed than climbed, eventually brought us to the bare rock of the wall.

We decided to attempt the true prow of the wall via the steepest, proudest line, mostly left of the 1973 route. Barricaded by a series of giant horizontal roofs with no continuous cracks, it looked unlikely to go free. Nevertheless, Wilson and I set to work climbing the first three rope lengths of the original route—to our surprise completely onsight—up to Tarantula Terrace, the site of Troy’s run-in with the eponymous arachnid.

Troy and his uncle, Edward James, had been indispensable thus far on this adventure, cutting the trail, helping find our air-dropped gear, and ferrying loads through the slime forest to the base of the wall. So, we were pleased when they accepted our offer to join us on the wall and climb to the summit with us, while the dozen other Akawaio helpers returned to Phillipai. Neither of our Akawaio friends had ever worn a harness. Back in Phillipai, Edward works as a subsistence farmer and hunter while Troy works as a laborer in Guyana’s grueling gold mining industry.

Waldo—an authority on all things related to ropes and rigging—had given them a crash course in jumaring, and they were now commencing the first Guyanese ascent of their country’s highest and most iconic mountain. They quickly figured out free-hanging jumaring, rappelling, and lowering out, a constant stream of laughter accompanying their efforts as they joked and bantered with each other. They wore ear-to-ear grins in their portaledge, clearly savoring the experience as they gazed out over the forest on the few clear days to the distant smoke rising from the cooking fires in the village they call home.

While Wilson and I pushed into terra incognita through giant roofs, our youngest crew member, Anna, set to work unlocking a way to free climb the 20m of beautiful blank rock alongside a bolt ladder drilled by the 1973 team. After three days of effort, she was rewarded with a free ascent of the most technically difficult pitch (5.12+) and best of the route. By that time, Wilson and I had discovered Invisible Ledge: perfectly flat, about 10m long and 1m wide, and obscured from even just a few meters below. Halfway up the wall, it provided a comfortable perch for our eight-person team.

The frequent tropical downpours might have thwarted our efforts to free climb, but the incredible steepness of the prow kept us and the route almost completely dry. Wilson and I continued upward, both climbing onsight, swapping leads and seconding free, until I neared the end of the steepest section of wall, ten pitches up. Unfortunately, after almost two hours on lead, my onsight efforts fell short less than a meter from easier ground.

After a couple of easier pitches, our line forced us around the corner onto the left side of the mountain, and in a single step I went from dry and calm into a ferocious wind and driving rain, exposing my body to hypothermic temperatures—something I never thought I’d experience just a few degrees from the equator.Returning a day later, I opted this time to tackle the beautifully sculpted arête of the prow and managed to climb into a position where a fall would have had dire consequences; I barely hung on long enough to drape a 3mm sling over a flake the size of coin, precariously hang for a rest, and pull up the drill to place a bolt. One pitch higher, Wilson brought us to the summit.

We still needed to free the couple of pitches that had thwarted our onsight attempt, and we achieved this over the next couple of days. Finally all eight of us celebrated our excellent adventure on top with our last bottle of Guyana’s celebrated El Dorado rum. This entire experience was particularly rewarding to share with our Akawaio friends, without whom we would have never made it to the base of the wall and who, without our help, could never have made it to the top.

Summary: First ascent of the Great Northern Prow (600m, E6 6c or 5.12+ R), with 14 pitches, 10 of them new, November 24–December 5, 2019. Like most previous parties, the team helicoptered off the top.