The encyclopedia has more than 45,000 articles, most of them more than 500 words and many running to considerable length (the "United States" article is over 300,000 words). The work's coverage of American and Canadian geography and history has been a traditional strength. Written by 6,500 contributors, the "Encyclopedia Americana" includes over 9,000 bibliographies, 150,000 cross-references, 1,000+ tables, 1,200 maps, and almost 4,500 black-and-white line art and color images. It also has 680 factboxes. Most articles are signed by their contributors.