Roedean Girls School is located on the cliff tops to the east of Brighton and separated from the beach by the busy A259. Around 1910 a tunnel was excavated beneath the road and led via steps to what is now Undercliff Walk. This was to allow the pupils to reach the beach safely for swimming and other maritime activities. There are 144 steps that desend to the lower level.
In World War II, the tunnel was used as an air-raid shelter, both by the girls and after requisitioning by the Navy as HMS Vernon. The school reoccupied the site after the war and the tunnel remains accessible but secure although it is rarely used.