The Pacific Ocean is so huge that it contains its own antipode.
The antipode of any spot on Earth is the point on the Earth’s surface diametrically opposite to it. Have you ever wondered which part of the other side of the earth is directly below you? If you have, you’ve thought about an antipode.
The Pacific Ocean is so big that if you dove and swam through the center of Earth, you’d still find yourself in the Pacific Ocean.