Lake Natron can turn the creatures that die in it to stone. Along this shallow lake in northern Tanzania, birds and bats that drown are calcified where they fall and left behind like pale statues. That is the root of a myth that the lake petrifies anything it touches. The real explanation is chemistry rather than a curse. Mineral hot springs feed the lake and it has no outlet to the sea. The water spreads up to 57 kilometres across the East African Rift but is barely three metres deep. In 40-degree heat it evaporates fast and grows thick with sodium carbonate, which pushes its pH to about 10.5, as caustic as ammonia. Salt-loving microbes thrive in that brine and stain it deep red, so from the air the lake appears as a sheet of crimson streaked with white soda.
Yet this lethal water is the single most important nursery on Earth for the Lesser Flamingo. Around three-quarters of the world's population hatch here, and nowhere else in East Africa. As the dry season ends, up to two and a half million birds gather on the flats and raise their young on soda islets, where the burning crust keeps every predator away. Stand on the shore at dawn and the shallows turn pale pink under the massed birds. On the horizon stands Ol Doinyo Lengai, which the Maasai call the "Mountain of God", and it erupts the coldest lava on the planet. Nearby, the Ngare Sero waterfalls run cool through a palm gorge, an oasis away from the salt glare. The basin has been a protected Ramsar wetland since 2001, but schemes to mine its soda for export keep coming back and being fought off, most recently in 2025. That struggle shows how fragile this place remains.