Mount Roraima is a tabletop mountain walled by cliffs 400 metres high at the point where Venezuela, Brazil and Guyana meet, the highest of the tepuis of the Guiana Highlands, and it is climbed over several days to a summit of black rock, quartz and constant cloud whose plants and animals exist nowhere else. The mountain is a slab of sandstone two billion years old, and its summit has been cut off from the world for so long that its life evolved alone: sun-pitchers and other plants that trap their own food because the rain strips the rock of nutrients, and a tiny black frog that cannot hop. In Pemón, tepui means house of the gods, and Roraima is the greatest of them, the stump of a mighty tree that once held every fruit and crop in the world until it was felled and the flood poured out. Arthur Conan Doyle put dinosaurs on it in The Lost World, and from the Gran Sabana below, with its walls rising sheer out of the grassland, the idea does not seem foolish.
The trek begins at the Pemón village of Paraitepui, the last point a road reaches, and crosses open savanna for two days with a licensed guide and porters to the foot of the wall, then climbs a ramp, the only weakness in the cliffs, to the summit in a day. The top is a maze: black rock carved by rain into towers and gullies, pools in round hollows that trekkers call the jacuzzis, and the Valley of Crystals, where clear quartz lies loose in clusters that crunch underfoot and flash when the sun breaks through. Nights are spent in what the guides call hotels, flat dry ground under sandstone overhangs, and a walk reaches the triple point where the three countries meet on a concrete marker. Cloud wraps the summit most of the year, clearing for minutes; the dry season from December to March gives the best odds. Roraima is a mountain with a lost world on top, and the world is still there.