The first tunnels under
Dover Castle were constructed in the Middle Ages to
provide a protected line of communication for the soldiers
manning the northern outworks and to allow the garrison
to gather unseen before launching a surprise attack.
During the Napoleonic Wars, this system of tunnels was
greatly expanded to fortify the Castle in readiness
for a French invasion. Seven tunnels (running with damp
and prone to collapse) were dug as barracks for the
soldiers and officers who were filling both castle and
town to overflowing. These were capable of accommodating
up to 2,000 troops. They are the only underground barracks
ever built in Britain.
In May 1940, as France fell before the German advance,
the tunnels became the nerve centre for
'Operation
Dynamo' - the evacuation of the British Expeditionary
Force (BEF) and French troops from Dunkirk's beaches.
Admiral Ramsay and
his staff worked round the clock for nine days. On 26
May some 400,000 troops were awaiting rescue on the
beaches of Dunkirk. The best estimate was that only
45,000 could be brought back. Yet, by 4 June, nearly
all were evacuated. In total, 338,000 men came back:
the BEF and 139,000 French soldiers.
In the Cold War the tunnels were further expanded to
form a Regional Centre of Government in the event of
nuclear war. With the fall of the Berlin Wall in 1989
the need for this facility decreased and in the early
1990s it was decommissioned and areas of the tunnels
opened to the public.