BLUE ISLAND, a city of Cook county (Illinois), U.S.A., 16m. S. of the Chicago Loop, on a ridge six miles long by two to three wide, which rises abruptly out of the prairie to a height of 4o-soft. It is on the Dixie highway and the Calumet Sag canal; and is served by the Rock Island, the Illinois Central, and five other railways. The population was 11,424 in 192o, and was 16,534 in 193o by Federal census. The Chicago freight yards of the Rock Island lines are situated here, as well as the division roundhouse and repair shops, and shops of other railways. There are large brickyards, a canning plant, and factories making steel and wire products, tile, and dental supplies. Blue Island was settled in 1835 and became a city in 1902.