SR 120 continues north onto Ballston, where the highway expands to six lanes at Quincy Street. The state highway passes by Ballston Quarter and the adjacent MedStar Capitals Iceplex, practice rink of the Washington Capitals. SR 120 veers north at Wilson Boulevard and passes by the Arlington Center of Northern Virginia Community College at Fairfax Drive, which heads east as SR 237 toward Clarendon and west as ramps to and from I-66 toward Falls Church. The state highway runs concurrently with SR 237 for two blocks north to Washington Boulevard, onto which SR 237 heads west toward Falls Church. Just north of Washington Boulevard, SR 120 has a partial interchange with I-66 that allows access to and from the direction of Washington and where the highway crosses the Custis Trail.