The word 'Obo' means 'forest' in the local Forro language. The park protects a very old, very wet rainforest where giant ferns, mosses and flowering trees grow so closely together that sunlight only reaches the ground in little flickering patches. Walking through it feels like being inside a green cave.
Because São Tomé and Príncipe were always islands - never connected to the African mainland - animals and plants that arrived here long ago slowly changed over thousands of years to suit island life. Scientists call these unique creatures 'endemic', meaning you will not find them anywhere else in the world.
Obo Natural Park is also one of the best places on Earth to spot the giant sunbird, a large colourful bird that sips nectar from flowers deep in the forest. Rare orchids, giant tree ferns and enormous snails also call the park home.
Rangers look after the park and make sure the forest stays healthy. Local school groups visit to learn about the plants and animals, and some of the rangers grew up in villages right next to the park's edge.