Borçka Karagöl is a black lake at 1,480 metres in the mountains of Artvin province, in the far northeast of Türkiye near the Georgian border, ringed by fir, spruce and beech that burn red each October, circled on a wooden walkway close to the water, and it is the picture of the eastern Black Sea's autumn, reached by a forest road from the town of Borçka that shuts with the December snow. The lake was made by a landslide that dammed a stream in the Colchic forest, and it is burying itself, since the two streams that keep it alive carry gravel and silt into a basin with nowhere to put it, so that trunks rise straight out of the shallow margins and lie half-sunk beneath the water; the boardwalk runs the whole way round, close enough to the water to watch the reflection change as the walker moves, with the near-black green of the Nordmann fir and oriental spruce mirrored in a lake that is black from its depth and the peat of its floor. From mid-October the beech and hornbeam ringing the lake turn yellow, orange and red against the conifers, peaking in the second half of the month and holding into November, doubled in the still water on a windless morning.
Stepping off the boardwalk into the forest above the shore is stepping into the wet Caucasian woodland that climbs away from the lake, fir and spruce over a thicket of rhododendron and ivy with cloud caught in the branches after rain, the Colchic forest that survives here from before the ice ages. Almost everyone photographs the big triangular lake and leaves, but a second smaller lake lies behind the north shore in the trees, and the lake sits on a migration corridor inland of the coast, with the most bird species passing in September. The first heavy snow settles in December and the black lake skins over. Borçka Karagöl is a black lake in a red forest, and the forest is slowly filling it.