Flag of Portland, Oregon (Wikipedia)
The city flag of Portland, Oregon, consists of a green field on which is placed a white four-pointed star (a truncated hypocycloid) from which radiate blue stripes, each bordered by L-shaped yellow elements. Narrow white fimbriations separate the blue and yellow elements from each other and from the green background. The official ordinance specifies a height of 3 feet and a length of 5 feet.
City ordinance 176874, adopted September 4, 2002, designates the design and its symbolism. Green stands for "the forests and our green City"; yellow for "agriculture and commerce"; blue for "our rivers".