Poulsen created the World Map between 1944 and 1969. It measures 45 by 90 metres (49 by 98 yards), covering an area of over 4000 square meters (1 acre). One 111-kilometre (69 mi) degree of latitude corresponds to 27 centimetres (11 inches) on the map. On Poulsen's map, Antarctica is not present and the Northern Hemisphere is marked in two places, ensuring a better impression of the correct distances between the countries to avoid the difficulties of spreading out our planet's globular shape. Red poles mark the equator, and each country is represented by miniature flags, which are updated yearly. State borders in the United States of America are marked with yellow bricks; Poulsen lived 20 years in America.