What is the oldest man made wall?
What is the oldest man made wall? The 23,000-year-old stone wall in front of Theopetra cave probably built to protect its residents from cold winds at the height of the last ice age, is the oldest known example of a man-made structure!
What is the oldest cave in the world?
The Geological History of the Jenolan Caves Scientists have determined, through the examination of the clay found in the caves, that the Jenolan subterranean system is around 340 million years old. This makes it the oldest known and dated open cave system in the world, and it is still being heavily researched today.
Where is the deepest cave on Earth?
(The absolute deepest known cave on Earth is the Veryovkina Cave in Georgia, at more than 6,800 feet deep.) The Hranice Abyss is located in a limestone formation in the Czech Republic. The stone face is full of holes worn away by acidic snowmelt, leaving it Swiss cheese-like, reports Science magazine.