On Nov. 11, 1918 at 11:00, the guns of World War I fell silent. This moment marked the end of the first great war of the 20th century. It wasn't the longest, but it was one of the bloodiest and most brutal. At the time, its inhumanity was legendary. Millions of young men marched off to war; the casualties numbered in the hundreds of thousands. Entire cities were reduced to rubble as the armies of Europe beat each other to bloody ruin.