Similar in scope to Fergus Fleming's Off the Map. Also covers many of the same explorers (Marco Polo, Cook, Humboldt, Peary, etc.), but Downs has a wider time period and includes some less well known names like William Bartram and Henry Schoolcraft and not nearly so much about polar explorers. Downs also focuses primarily on the explorers' own books and journals, citing very few secondary sources. Overall, an enjoyable book, recommended for people who enjoy travel and adventure stories.