A charming littler artistic town, Mosier is most popular for the Mosier Twin Tunnels hiking trail. The area was first settled by white Euro-Americans in 1854 and became a city in 1914. They built a post office here, then the Mosier School in 1920, which later became a charter school known as the Mosier Community School in 2003. The town is approximately .64 square miles. It is downstream of the 18 mile island and was along the Columbia River Highway long ago. Today, the 96 oil car derailment that caused a natural disaster on June 3, 2016 has placed Mosier on the map.