The first contingent of US troops to be deployed in northern Australia under a new bilateral defence deal, landed in Darwin on Tuesday night to start a six-month rotation.
About 200 US Marines from Fox Company, 2nd Battalion, 3rd Marines were welcomed by Defence Minister Stephen Smith when they arrived just before midnight.
An official welcome for the marines will be held at the barracks on Wednesday.
The unit, which has recently been on active service in Afghanistan, will be based at Robertson Barracks on the outskirts of Darwin. The ABC reports they will use ADF training areas at Mount Bundy and Kangaroo Flats
By 2017, 2500 US marines will be deployed in northern Australia in the dry season.