Churchill&rsquos wartime tunnels at White Cliffs in Dover are now open to the public. Built during WWII after a red-faced Churchill found that enemy ships could freely sail through Dover, this network of tunnels was constructed in just 100 days. Excavated and restored, they&rsquore still in very good shape. As you walk through these tunnels, you&rsquoll get a sense of what life was like during the war, and the graffiti on the walls will give you an insight into the soldiers&rsquo minds and milieu. Time to go underground. nationaltrust.org.uk