What Are U Shaped Valleys? A U-shaped valley is an geological formation that has steep, high sides and a rounded or flat valley bottom. They result from glaciation and are often filled with lakes, rivers and sand traps on golf courses, kettle lakes (water hazards), and other such natural features. https://wwwsofasandcouchescom53029.thekatyblog.com/29090523/why-all-the-fuss-sectional-u-shape