Watch: unseen footage of Titanic wreck from a 1986 dive video

Rare and in some cases never before publicly seen video of the 1986 dive through the wreckage of the Titanic is being released by the Woods Hole Oceanographic Institution.

The more than 80 minutes of footage on the institution's YouTube channel on Wednesday chronicles some of the remarkable achievements of the dive led by Robert Ballard.

The expedition marked the first time human eyes had seen the giant ocean liner since it struck an iceberg and sank in the frigid North Atlantic.

The vessel met its fate on its maiden voyage from Southampton, England, to New York City in April 1912.

About 1,500 people died.

The vessel now lies in some 2.4 miles below the surface of the ocean.

Technical limitations as well as the vast expanse of the search area in the North Atlantic made it impossible to locate the wreck.

By 1985, WHOI had developed new imaging technology, including Argo, a camera sled that was towed from the research vessel Knorr and captured the first photographs of the ship beneath more than 12,400 feet of water.

The footage was released to mark the 25th-anniversary debut of the Academy Award-winning movie, “Titanic.”

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