The discovery and mapping of the world, its peoples, oceans and continents, are the result of centuries of exploration.This book traces the history of such travel and the pioneers who pushed back the frontiers of the known world.It explains the reasons for their journeys, whether out of scientific curiosity, to create trading opportunities, to spread religious beliefs or for personal gain or glory.With the aid of over 250 illustrations, maps and photographs, this accessible reference work captures all the excitement and spirit of adventure.