In 2016, researchers made an incredible discovery deep down within a Canadian mine. They found the world's oldest pool of water at a depth of approximately 3 kilometers or 1.8 miles. The water dates back to a stunning 2 billion years old, breaking the record for the oldest known water by at least 500 million years. The previous record was held by water found in the same mine by … [Read more...] about 2 Billion-Year-Old Water: World’s Oldest Pool of Water Discovered in Canadian Mine