Derna was captured in 1805 by a force led by William Eaton and Presley O'Bannon during the First Barbary War. The episode became famous in the United States as part of Marine Corps history, echoed in the line "to the shores of Tripoli."
There is no tidy battlefield park to visit. The point of the stop is historical orientation: Derna's harbour, old town and approaches help explain why the city mattered in Mediterranean politics long before Libya became a modern state.