A few yards away from the historic Marconi hut Penarth's only World War II Royal Observer Corps (ROC) Searchlight post stood on the cliff edge with its clear views over the Bristol Channel and the islands of Steep Holm and Flat Holm. The Observer Corps site was established by the Air Ministry on part of the original War Department land connected to the Lavernock Gun Battery. The volunteer ROC observers spotted many Nazi German Luftwaffe raids approaching across the channel and activated the air raid warnings in the town.