Lake Ritsa is a deep green-blue lake in the Western Caucasus at 950 metres, ringed so closely by relict beech, fir and spruce that the forest comes right down to the waterline. It runs about 2.5 kilometres long and reaches 116 metres deep, and it changes colour through the year — yellow-green in spring, deepening to blue and emerald by autumn. That shift has nothing to do with glacial rock flour. It comes from blooms of microscopic plankton and from how clear the feeder rivers happen to be running, so the same water can look like a different lake from one season to the next. The lake is young. Only a few centuries ago a slope of Mount Pshegishkha collapsed, likely shaken loose by an earthquake, and dammed the Lashipse River behind a wall of rock more than a hundred metres high.
Reaching the shore means a slow drive up the Bzyb River gorge, past a tiny, intensely blue lake and through the Yupshara Canyon, where the cliffs close to about twenty metres apart. At the lake, wooden jetties and red catamarans wait along the waterline; in the early morning the surface lies like glass and holds the inverted ridges, and by afternoon a breeze breaks it into scattered light. The mountain air smells of pine and stays cool — even in August the water barely passes 17°C. On the shore stands one of Stalin's favourite summer dachas, built in 1947 and open to visitors today. One thing shapes any trip here. Ritsa lies in Abkhazia, a breakaway region that most of the world still recognises as part of Georgia, and in practice the only working route in is from the Russian side near Sochi. Georgian law counts that as illegal entry, and it can get you refused entry to Georgia afterwards.