The impact of Christopher Columbus's first transatlantic voyage launched an unprecedented explosion of European exploration. Throughout the last 500 years, scholars have recognized this transforming event, and they have written extensively on the subject. To date, no American author has dedicated a book to Columbus's life before 1492. This book is a biography of Christopher Columbus prior to 1492, with a focus on those geographical experiences that affected his formulation of a transatlantic concept. Incorporating extensive research from American and European scholars (historians, geographers, anthropologists, and cartographers), the author proposes that Columbus systematically built a transatlantic voyage proposal from knowledge gained on previous voyages in the Mediterranean Sea and Eastern Atlantic Ocean. The extensive use of maps place Columbus's actions on specific geographic land and ocean locations. The curious public, especially persons interested in gleaning more information about Columbus's maritime background, will find a plethora of maps to visualize the extent of his early travels.