Dubuque is a city in Dubuque County, Iowa, United States, and its county seat. The population was 59,667 at the 2020 United States census. The city lies along the Mississippi River at the junction of Iowa, Illinois, and Wisconsin, a region locally known as the Tri-State Area. It serves as the main commercial, industrial, educational, and cultural center for the area. Geographically, it is part of the Driftless Area, a portion of North America that escaped all three phases of the Wisconsin Glaciation, resulting in a hilly topography unlike most of the Midwestern United States.