The wall was discovered off the coast of Brittany. The wall measures an average of 65 feet wide and just 6.5 feet high, and is covered by 30 feet of water. The excavated settlement was similarly flooded by rising sea levels after the last ice age and “was positioned directly at the coastline,” as underwater archaeologist Peter Moe Astrup told the Associated Press at the time. “What we actually try to find out here is how was life at a coastal settlement.”According to the archaeologist, sea levels rose by around 6.5 feet per century approximately 8,500 years ago. More on the ice age: Ice Age Humans Were Skilled Firebenders, Scientists Find