U.S. Army first armored Division for cross country maneuvers at the Fort Knox military base in Kentucky, United States, shortly before America's entry into World War 2. Aerial view of tanks on ground. U.S. fighter aircraft in formation flight. Tanks move on ground. Army soldiers on motor bikes or motorcycles. Soldiers of the U.S. first armored division in boats crossing a water way. Water splashes as bombs are being dropped in practice battle drills. Soldiers climb a hill. Tank moves on an uneven ground. Tank smashes a trees. M2 Light Tanks and M2A1 Medium tanks smashing into trees, small houses, and shed buildings.