In this episode of Backyard Geology, Serena takes you to Regina, Saskatchewan to explore one of the greatest puzzles in Canadian geologic history. The Trans-Hudson Orogeny was a massive Paleoproterozoic mountain building event that built a large portion of North America. Over a billion years of erosion now conceals the Himalaya-sized event in the flat landscape of the Canadian prairies. Learn about how the movement of continents has changed over time and how North America came together through a spectacular accretionary event.