Messages of mysterious origin found embedded in asphalt in about two dozen major cities in the United States and three South American capitals. 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 on the above inscription. Some of the more elaborate tiles also feature cryptic political statements or exhort readers to create and install similar tiles of their own.
The material used for making the tiles was long a mystery, but evidence has emerged that they may be primarily made of layers of linoleum and asphalt crack-filling compound. Wrapped in tar paper and placed on a busy street early in the morning, the pressure exerted by automobiles pushes it into the road surface. Eventually, the tar paper wears away, exposing the message.
A tile that used to be located in Santiago de Chile mentions a street address in Philadelphia, Pennsylvania: 2624 S. 7th Philadelphia, PA. The current occupants of the house know nothing about the tiles and are annoyed by people who ask.
