Large construction projects at SFO, a department of the City and County of San Francisco, are often funded through the issue and sale of municipal bonds. Between the 1930s to the 1970s, the Airport issued bonds, printed on “bond” or bank paper, to finance such improvements. Several examples from projects over the years are included in our collection, as showcased here. Bonds today are issued electronically and not printed, so old paper bonds are considered collectible. Do you have any paper bonds? This image was posted on July 27, 2018.