McLean is situated in northeastern Fairfax County within the Piedmont region of Virginia. It is bounded to the north and east by the winding Potomac River, which serves as the natural border between Virginia and Maryland. To the south lies the city of Falls Church and Arlington County, while the commercial district of Tysons borders it to the west.
The geography is distinctly green and lush, heavily populated by mature deciduous forests. McLean's proximity to the Potomac River provides it with a series of winding creeks, streams, and protected natural corridors, most notably Difficult Run and Pimmit Run. These waterways carve through the landscape, contributing to the area's natural beauty and supporting local wildlife.