St. Helens is both the most populous city in Columbia County and the county seat. Named after the mountain across the river, the city sits along U.S. 30 and the Columbia River between Scappoose and Columbia City. It is home to the county’s historic courthouse, which has a lovely waterfront park next door. Though the historic downtown is a bit of a maze to get to, as it is not right off of U.S. 30. It was once thought of as a bit of a rival to Portland in the early days of the state due to its location on the Columbia River.