One man spent decades transforming a barren Kenyan quarry into a wildlife sanctuary

A landscape near Mombasa, Kenya, once looked almost impossible to restore. Decades of limestone quarrying had left the ground hard, hot and largely devoid of vegetation, while salty groundwater made growing plants even more difficult. Then Dr René Haller, a Swiss-born naturalist and agronomist working with Bamburi Cement, began an ambitious experiment in ecological restoration. Starting in the early 1970s, he tested plants, rebuilt soil and studied how organisms could work together to bring life back to the exhausted quarry. What followed was a decades-long transformation. The barren industrial site gradually developed into forests, wetlands, ponds and habitats for wildlife, eventually becoming what is now known as Haller Park.The Kenyan quarry left barren by limestone miningBamburi Cement began quarrying limestone near Mombasa in the 1950s to supply its cement works. By the early 1970s, large areas had been heavily altered by extraction. The quarry floor was described as barren and hard, with temperatures reaching about 40°C, while saline groundwater created another major obstacle for plants.The challenge was not simply to plant trees. The land had lost much of the biological syst...