US troops pulling out of Afghanistan
31 January 2014 Last updated at 11:53 GMT
The withdrawal of foreign forces from Afghanistan is gathering momentum and by the end of 2014 all combat troops are scheduled to have left.
It is proving to be a hugely challenging operation with US troops alone taking with them 218,000 items of military equipment.
David Loyn was able to spend time with some American troops as they left Bagram airbase for the last time.