Diosso Gorge is an amphitheatre of red clay cliffs sunk into the coastal forest of the Kouilou department in the Republic of the Congo, twenty kilometres north of Pointe-Noire, walls of ochre, pink and cream sand up to fifty metres deep that are still crumbling and growing with every rainy season, with the kings of Loango buried on its rim, and it is walked along the lip, climbed into on ladders that the village youth built, and followed down to the Atlantic. The cirque was cut by the rains out of the soft sand and clay of the coastal plateau, and the heaviest months, over 200 millimetres in a single month, pour off the plateau and cut fresh gullies, which is how the amphitheatre keeps widening; some columns stand clear of the cliffs held up by their own hats, a cap of harder iron-cemented ground sheltering the soft sand beneath while the rest washes away, and worn paths run along the lip, each bend bringing a fresh stretch of coloured wall into view, best in the wet months, when sun and rain arrive together and the low light sets the hematite reds burning, since a cold ocean current keeps a layer of cloud over the coast through the dry season and the walls go pale.
The way in is on homemade paths and ladders that the Diosso youth association built and maintains, with a guide from the village, and a longer trail leaves the rim, drops through the forest on the floor and follows the gorge to the sea, about ninety minutes down and a harder climb back. A few minutes from the rim in Diosso village lies the burial ground of the kings of Loango, who ruled this coast from about 1550 for three centuries, and whose bay below their capital grew into one of the busiest embarkation points of the Atlantic slave trade, told in the museum of the last king's house beside the graves. Diosso is a canyon the rain is still digging, and the kings who traded from its coast lie on its edge.