What cave, found in central Kentucky, is the world's longest cave system?

More Questions:

Who was born Mark Feld?

In what year did Joseph Smith first organize the Mormon Church?

Which literary work's title character is named Edmond Dantes?

Who wrote the famous poem "The Waste Land"?

What is the capital of the Tonga?

In the human body, what does the ureter carry?

What plastic did John Wesley Hyatt invent by combining cellulose and alcoholized camphor?

Filbert is an alternative name for which nut?

What vitamin was isolated from fish liver oil in 1917?

What pop group sang "Stayin Alive"?

What kind of animal did Matt Damon voice in the 2002 movie "Spirit"?

What was rapper Eminem's first album titled?

John Paul Jones was bassist and keyboardist for what rock band?

What was President Truman's first name?

What is the capita of Greenland?