Not far from the present-day golf course, the remains of a network of training trenches from the World War I era can still be found. Quantico was established for the purpose of training Marines, especially officers, to fight in the first world war, when trench warfare was at its height. - Not far from the present-day golf course, the remains of a network of training trenches from the World War I era can still be found. Quantico was established for the purpose of training Marines, especially officers, to fight in the first world war, when trench warfare was at its height.