In an area between Mount Rainier and Mount St. Helens in Washington State sits a grassland expanse of naturally formed goosebumps known as mima mounds ranging from two to seven feet tall and up to 40 feet across. Despite research and monitoring over the last 50 years, the origin of these rare land formations has baffled scientists. Theories that have been published and debated include that they were built by pocket gophers; the result of wind-blown sediment being ensnared by vegetation; formed by glacial meltwaters; the result of earthquake waves; or the sediment from a glacial outburst flood that swept through the valley 17,000 years ago. No matter what created the mounds, visitors to the Mima Mounds Natural Area Preserve would agree the spring bloom of the purple camas flowers is a beautiful sight.