MV Pocahontas from Gravesend across the Thames to visit historic Tilbury Fort.
Founded by Henry VIII it has been defending London and the Thames estuary for a timespan that covers both The Armada and the Second World War with its Blitz.
shoot down a Zeppelin in the First World War.
famous speech to rally the troops against the threatened Spanish invasion.
It's quite impressive and worth visiting though alas the famous Water Gate was closed as it had become dangerous (and also was flooded).