It happened around 9:45 p.m. Tuesday night in the 13400 block of Mercersburg Road.
The Washington County Sheriff's office says a 2014 Honda was traveling westbound, left the roadway and slammed into a tree.
The driver, Cory Lynn Clark, was initially transported to Meritus Medical Center but was later taken to Baltimore Shock Trauma.
Investigators say speed was a factor in the crash.
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