The 4th Infantry Division is a modular division of the United States Army based at Fort Carson, Colorado. It is composed of four organic Infantry and Armored Brigade Combat Teams. The 4th Infantry Division's official nickname, "Ivy", is a play on words of the Roman numeral IV or 4. Ivy leaves symbolize tenacity and fidelity which is the basis of the division's motto: "Steadfast and Loyal". The second nickname, "Iron Horse", has been adopted to underscore the speed and power of the division and its soldiers.