Our oceans are home to more than 90% of all living creatures. With many hidden deep on the ocean floor, a submersible is the only way to reach them. Scientists in used the submersible, Alvin, to make amazing discoveries, including these ancient deep-sea coral reefs recently discovered within the Galápagos Marine Reserve. Recently upgraded, this 3-person submarine can dive to depths of 4 miles or 6500 meters, giving it access to 99% of the ocean floor, and scientists a front-row seat to some spectacular seafloor terrains and phenomena.