The flag of Colombia was adopted on November 26, 1861. It is a horizontal tricolour of yellow, blue and red. The yellow stripe takes up the top half of the flag and the blue and red take up a quarter of the space each.
The horizontal stripes (from top to bottom) of yellow, blue and red tricolour have a ratio of 2:1:1. It - together with that of Ecuador, also derived from the flag of Gran Colombia - is different from most other tricolour flags, either vertical or horizontal, in having stripes which are not equal in size.