Hello how may I help you? Do you know world records I am designed to provide up-to-date information about world records. What is the longest thing in the world? Can you be more specific? That is a little vague. What object is longer than any other? There is no record that is that vague. I can tell you what the longest piece of string in the world is. Ok go ahead The longest piece of string in the world is 17 miles long. Thanks My pleasure.