The Marines will be stationed in Darwin for training for the six months of the Top End's dry season. They are the fourth rotation since former prime minister Julia Gillard and US president Barack Obama struck a deal in 2011 to gradually increase the number of US Marines rotating through Darwin to 2,500 troops by 2017. A small ceremony was held at Darwin Airport with America Galaxy C5 as aircraft carrying CH-53E Super Stallion helicopters from Guam in Central America touched down. "We're coming from all over the globe," Lieutenant Colonel Eric Dougherty of the US Marine Corp said. He described the rotation in which US Marines will live and train at the Australian Defence Force's Robertson Barracks as "unique". "Most places we go to a different country and have our own base there. We're operating inside the base," he said. "But here we're going to be living inside the barracks. "You guys have opened up your homes to us. We're living in your guest house." Lt Col Dougherty said the training opportunities in the Northern Territory were a big drawcard. "You have some world-class training facilities here," he said. "Bradshaw training area (south-west of Darwin) is three times the size of anything we have in the States. "The outback truly is out back, with vast wide open spaces. "There's things we can do here we cannot do back in the States."