The sketchbook has been the one constant in explorers’ kits for centuries of adventure. Often private, they are records of immediate experiences and discoveries, and in their pages we can see what the explorers themselves encountered. This remarkable book showcases 70 such sketchbooks, kept by intrepid men and women as they journeyed perilous and unknown environments—frozen wastelands, high mountains, barren deserts, and dense rainforests—with their senses wide open. Figures such as Charles Darwin and Sir Edmund Hillary are joined here by lesser-known explorers such as Adela Breton, who braved the jungles of Mexico to make a record of Mayan monuments. Here are profiles, expedition details, and the artwork of pioneering explorers and mapmakers, botanists and artists, ecologists and anthropologists, eccentrics and visionaries. Here is the art of discovery.