St Michaels Caves are situated at the top of the Rock of Gibraltar in the Upper Rock Nature Reserve. The Cathedral Cave is where concerts are held on a regular basis. There are many events held in the caves, and during the war, they decided that the cave would act as a hospital, although this never happened in reality. The stalagmites and stalagtites that enhance the appearance of the caves are lit up by backlights in colours ranging from reds to blues. The cave has connecting passages to smaller caves, and is set out in the main as an auditorium.