Looking Down in Seattle – began in 1975 after Seattle Arts Commissioner Jacquetta Blanchett traveled to Florence and saw the city’s hatch art. Working with Department of Community Development director, Paul Schell, Blanchett donated enough money to fund 13 covers, with six more paid for by other donors. Each cost $200 and weighed 230 pounds. There are now numerous designs adorning Seattle’s streets.

Source: My Favorite Maps – by David B. Williams