This cache is NOT at the posted location. The eponymous adventure lab cache which starts in Washington DC, just outside of Ford’s Theater is needed here. Completing stage four will provide the coordinates for this bonus cache. This cache is located between stage four and five and is near Pope’s Creek Maryland; near where John Wilkes Booth and David Herold set out for the Virginia shore during the night of April 21, 1865. The fifth stage of the adventure lab is just south of Port Royal Virginia.
https://adventurelab.page.link/JxQC