Dinosaurs inhabited every part of the globe, with their remains found even in places like modern-day Belgium, because their reign began when Earth's landmasses were joined as the supercontinent Pangea around 230 million years ago. Throughout the 165 million years that dinosaurs existed, this massive landform gradually broke apart. The ongoing process of plate tectonics drove this continental drift, eventually scattering dinosaur habitats across the forming continents we recognize today.