Here's the sheet music for the oldest song in the world:

The song was discovered in the ancient Syrian city if Ugarit in the early Fifties, and then deciphered by Professor Anne Draffkorn Kilmer. The tablets containing the notation were about 3400 years old, and contained cuneiform signs in the hurrian language that provided musical notation of a complete cult hymn. It's thought to be the oldest preserved song with notation in the world, and predates the next earliest example of harmony by 1,400 years.

n 1972, Kilmer, who is professor of Assyriology, University of California, and a curator at the Lowie Museum of Anthropology at Berkeley, developed an interpretation of the song based on her study of the notation. She wrote a book (Sounds From Silence) about her quest, which comes with a CD recording of the song: Link

You can listen to it yourself. Here is a midi version: download the oldest song in the world