Discover why each of these 12 intrepid explorers risked everything to conquer the great unknown.

Explorers have transformed the world with their curiosity. But with great knowledge comes great responsibility, and thriving on adventure has often lead to great danger.

The explorers profiled here will give younger readers a fascinating survey of the history of this most dramatic of pastimes. The themes that are explored are: what motivated these explorers? What were they looking for, and what did they actually find? How did their journeys change their lives and the lives of the people they met?

The explorers included are:

• Samuel de Champlain
• Marco Polo
• Henry Hudson
• Christopher Columbus
• James Cook
• Hernán Cortés
• Lewis and Clark
• John Franklin
• Erik the Red and Leif Eriksson
• Roald Amundsen