In this paper, a multiple depot, multiple traveling salesman problem is transformed into a single, asymmetric traveling salesman problem if the cost of the edges satisfy the triangle inequality. This improves on the previously known transformation for a 2-depot, multiple traveling salesman problem in the literature. To test the effectiveness of the transformation, some computational results are presented by applying the well known LKH heuristic on the transformed problem for instances involving Dubins vehicles. Results show that the transformation is effective and high quality solutions can be found for large instances in a relatively short time.