The Washington Post reported that the image could be that of screen femme fatale Theda Bara, who epitomized the vamp (female vampire) image and was a huge star during the silent age of cinema.

Forty-five feet below the iconic sculpture of the former president is the sketch of a woman suspected to be Theda Bara — a scandalous silent film star from the time of the Memorial’s construction.

An artist’s sketch of a woman hidden on concrete walls deep in the undercroft, or basement, of the Lincoln Memorial for over a century may be graffiti of the early film star Theda Bara ...

Century-old graffiti under the Lincoln Memorial may depict silent-film star Theda Bara, with a profile sketch and the word "Vamp" found on the pillars in the basement. National Park Service ...