The Toynbee tiles (also called Toynbee plaques) are messages of unknown origin found embedded in the asphalt of streets in about two dozen major cities in the United States and four South American cities. Since the 1980s, several hundred tiles have been discovered. They are generally about the size of an American license plate, but sometimes considerably larger. They contain some variation of the following inscription:

TOYNBEE IDEA

IN MOViE `2001

RESURRECT DEAD

ON PLANET JUPITER