Mechanicsville is an unincorporated community and census-designated place (CDP) in Hanover County, Virginia, United States.

In addition to Rural Plains, Clover Lea, Cold Harbor National Cemetery, Cool Well, Hanover Meeting House, Hanover Town, Immanuel Episcopal Church, Laurel Meadow, Locust Hill, Oak Forest, Oakley Hill, Selwyn, and Spring Green are listed on the National Register of Historic Places.

Hill launched a series of assaults against Union Major General Fitz John Porter's army positioned along Beaver Dam Creek, just east of Mechanicsville.

Union forces repulsed the Confederate attacks and afterward withdrew to a new position along Boatswain Creek near Gaines' Mill.

The area identified as part of the battlefield for "Second Cold Harbor" stretches from near the intersection of Walnut Grove Road and Mechanicsville Turnpike to "Turkey Hill" near the Rt.

Mechanicsville comprises the western portion of Hanover County's southern extension, north of the Chickahominy River.

The southern border of the CDP, which follows the Chickahominy, is the Henrico County line, and at its closest point, Mechanicsville is less than two miles from the city limits of Richmond.

The CDP also includes the neighborhoods or named places of Pearsons Corner, Oak Forest, Kings Charter, Rural Point, Borkeys Store, Burnside Farms, Mayfield Farms, Carneals Store, Pole Green, Newman, Dogwood Knoll, Spring Meadows, Brandy Creek Estates, Windy Hill Estates, Ellerson Mill, and Simpkins Corner.