Of the strongholds which the Spanish built to maintain their title to this part of the world there remain such substantial relics as the old fort at St. Augustine, annually visited by thousands of people, and that at Pensacola, Florida. The French are best remembered by their works at Quebec. Of the defensive works of the Dutch, on the Hudson, or the Swedes, on the Delaware, nothing remains. The English were not great builders of forts; they were essentially tillers of the soil. The most important English military work of early Colonial days in America was Castle William (Fort Independence), Boston harbor. To the French with their restless explorers and indefatigable missionaries to the Indians must be ascribed the credit of most completely grasping the physical conditions of the North American continent and of formulating the most comprehensive scheme for military defense of their holdings. The French forts extended in a well-organized line from the mouth of the Saint Lawrence west and south through the Great Lakes and down the Mississippi to the Gulf of Mexico. They originated and executed, all things considered, the most daring and comprehensive military project ever conceived on the continent of North America. In the preparation of this work it has given me great pleasure and has clarified to a marked degree my conceptions of the larger movements of American history,--especially in regard to the topographical considerations governing these movements,--to have visited the seats of early empire in this country and the various centres of military renown in its later days. All of the places described in this book are worth a visit by the sight-seer as well as the historian--that is, they contain visible monuments of the Past. I have, myself, taken the greater number of photographs which illustrate the volume. Others have been donated or purchased, as the credit lines will tell. It is, perhaps, as well to state that this work has been done with the knowledge of the War Department of the United States, which has very kindly allowed me to reproduce some of the pictures in its archives and has greatly helped me with my researches in its public records. When I have visited those few points of historic significance still occupied by the army I have been very courteously shown all points of interest not of present military value and have been allowed to photograph scenes which I desired to record which would have no worth to an enemy of the country.