Wilmington is the county seat of New Castle County with a Year 2000 population of 491,409, and is located midway between New York City and Washington, DC, 30 minutes south of Philadelphia. The city lies between the Christina and Brandywine rivers, along Interstate 95 on the banks of the Delaware River. It is near Brandywine Creek State Park and Bellevue State Park, and is the gateway to the Brandywine Valley's world-class museums, gardens and cultural attractions.

Wilmington is part of the Wilmington-Newark, Delaware-Maryland metro area.