In 1985, The relics of Coastal Defense of Ming Density in Bangchui Island was discovered during the second national cultrual relic survey. It was identified by the cultural relics departments as a military facility site built in the Ming Dyn-asty to protect from foreign invasions. The Site is about 113 meters long and 10-13 wide, which was built of sediment rock nearby. It was shaped in a semi-circle along the easy slope of the north and west, and located close to the top of the hills, 43.6 meters above the sea level. It sits above steep surfaces and hard to be attacked. Its east and southwest sides ended along cliffs.