WASHINGTON – Covering more than 70 percent of the planet’s surface, the ocean is both a life-giving resource and a highway. Yet it is also a life-threatening obstacle, hiding untold mysteries.

Now the scholarly, or those just curious, can plumb the depths of the seas with the opening Saturday of the new Sant Ocean Hall at the Smithsonian’s National Museum of Natural History in Washington.

The $49 million project – the biggest renovation since the museum opened in 1910 – combines the tradition of a Tlingit canoe, the massiveness of a full-size whale model, the detail of hundreds of marine specimens and modern technology to tell the tale of the sea.

“For thousands of years people looked across the ocean and asked, ‘What lies beyond?’ Today we ask, ‘What lies below?’ and ocean explorers with new technologies are finding answers to those deep mysteries,” Conrad C. Lautenbacher, head of the National Oceanic and Atmospheric Administration, said.

Added museum director Cristian Samper: “The ocean is a global system essential to all life, including yours.”

The hall also is the only place in the world to exhibit the preserved remains of both an adult coelacanth and its pup. This large prehistoric fish was thought to have gone extinct 65 million years ago, until a fisherman caught one off the coast of South Africa in 1938. Other preserved remains include male and female giant squids.

But plenty of life is also on show, with a 1,500 gallon (5,680 liter) aquarium containing an Indo-Pacific coral reef featuring more than 1,000 specimens of 50 species of live fish and other marine life.

Overhead looms Phoenix, a 45-foot(14-meter) model of a live right whale which was born in 1987 and has been tracked by scientists ever since.

“Phoenix is the ambassador of the hall,” said Samper, who added that development of the hall took five years and involved more than 1,000 people.