The Marshall Islands are made up of 29 coral atolls and 5 islands spread across a huge stretch of the Pacific Ocean. To travel between them, ancient navigators needed to find their way across hundreds of kilometres of open water. They solved this challenge by studying how the ocean itself moves.
When ocean swells - long rolling waves - hit an island or atoll, they bend and bounce in a pattern. Skilled navigators learnt to feel these patterns through the hull of their canoe or by lying flat and sensing the rocking. Stick charts were teaching tools: the curved bamboo sticks showed where swells bent around islands, and the shells marked where the islands were.
There are different kinds of stick chart. Some were personal learning maps used only by one navigator. Others were teaching charts shared between families. The knowledge inside them was precious and was passed down through generations as a treasured skill.
Today, stick charts are one of the most famous inventions of the Pacific. They are displayed in museums around the world, and Marshallese artists still make them as a way of celebrating their ancestors' brilliant minds.