Ellicott City Historic District is a national historic district in Ellicott City, Howard County, Maryland. The Ellicott City Station is a National Historic Landmark located within the district. The district encompasses a predominantly 19th century mill town whose origins date to 1772, including more than 200 18th- and 19th-century buildings. It was listed on the National Register of Historic Places in 1978. The district was severely impacted by the 2016 Maryland flood on July 30, 2016.