Allan's Island Radar Station - Credit: Wikimedia Commons
Allan's Island Radar Station (Cinco) was a United States Army General Surveillance Ground Radar Early Warning Station in the Dominion of Newfoundland. It was built during World War II and responsible for monitoring air traffic from Naval Station Argentia to Gander and into the Gulf of St. Lawrence. It was located on Allan’s Island southwest of St. John's. It was closed in 1945. Read more on Wikipedia
Source: en.wikipedia.org