According to the United Nations, Sierra Leone is one of the countries most exposed to coastal erosion. More than two million people are threatened by rising sea levels. Even the capital, Freetown, and its informal settlements – built by reclaiming land from the sea – are on the brink of sinking. A phenomenon caused by climate change, but exacerbated by human activity. Submersion is accelerated by the country's extreme poverty, which pushes the population to destroy their environment in order to survive. FRANCE 24's Caitlin Kelly, Saidu Bah, Sarah Sakho and Simon Martin report.