Marines and Sailors with the 31st Marine Expeditionary Unit ride elephants during a tour of elephant village Feb. 22. Service members were enjoying some much deserved liberty at the conclusion of the 30th annual Cobra Gold exercise. For three decades, Thailand has hosted Cobra Gold, one of the largest land-based, joint, combined military exercises in the world, which started out as a bilateral exercise, but has since grown to include Japan, Indonesia, Singapore, Malaysia and South Korea as full participants and dozens of other countries as official observers. - Marines and Sailors with the 31st Marine Expeditionary Unit ride elephants during a tour of elephant village Feb. 22. Service members were enjoying some much deserved liberty at the conclusion of the 30th annual Cobra Gold exercise. For three decades, Thailand has hosted Cobra Gold, one of the largest land-based, joint, combined military exercises in the world, which started out as a bilateral exercise, but has since grown to include Japan, Indonesia, Singapore, Malaysia and South Korea as full participants and dozens of other countries as official observers.