Live: Watch the National Museum of African American History and Culture Grand Opening Dedication Ceremony

Free from their mother's care, five young lions must fend for, and feed, themselves. Their first challenge: a giant giraffe who refuses to be caught.

Incredible: Five Lions Take Down a Giraffe (2:49)

Just outside North Carolina's Outer Banks is Roanoke Island, the scene of one of the greatest unsolved mysteries in U.S. history: the disappearance of an entire colony of English settlers.

The Colonial Settlement That Vanished Into Thin Air (2:10)

Prepare to be amazed.

Ask Smithsonian: What’s a Stone Baby? (1:07)

The superheros creator, William Moulton Marston, was a Harvard-trained psychologist and inventor and infused his daily life into the comic book.

The Origin Story of Wonder Woman (4:36)