The Tri-Cities of Virginia (also known as the Tri-City area or the Appomattox Basin) is an area in the Greater Richmond Region which includes the three independent cities of Petersburg, Colonial Heights, and Hopewell and portions of the adjoining counties of Chesterfield, Dinwiddie, and Prince George in south-central Virginia.

The Tri-Cities area is centered on the Appomattox River about 25 miles (40 km) south of Richmond.

Amtrak passenger railroad service is provided with a station at Ettrick, an unincorporated community in Chesterfield County adjacent to both Petersburg and Colonial Heights.

There are nine routes serving parts of Petersburg, Ettrick, Colonial Heights (Southpark Mall area), Fort Gregg-Adams, and Prince George County that all have their intersection in Old Town.

Built in 1988 at the intersection of State Route 144 and Interstate 95, the mall complex has expanded significantly to include many big box retailers.

Despite its name, the address of the Petersburg Federal Correctional Complex is actually in Prince George County.

In addition, there is United States Probation Office near FCI – Petersburg, in Colonial Heights, Virginia, and the two agencies enjoy a supportive relationship.

Puddledock Sand & Gravel, in Prince George County, Virginia is a quarry that has made significant alteration of the landscape along the Appomattox River and State Route 144 (Temple Avenue).

Many sites in the Tri-Cities area have names reflecting the region's role in the American Civil War.