Toynbee tiles

Messages of unknown origin found embedded in asphalt of streets

The Toynbee tiles, also called Toynbee plaques, are messages of unknown origin found embedded in 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:

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