Panorama reporter Jane Corbin travels to Iraq to see how the British forces are operating three years after the invasion.
There are 8,000 UK forces still in Iraq. The British entered Basra in April 2003 and are still a presence there today.
The priority for British forces is the gradual handover of security to the Iraqi police and army.
Helicopters are a vital means of transport. They are used to ferry servicemen over unsafe roads below.
Although southern Iraq is relatively peaceful compared to the rest of the country, the British often come under attack.
It is a full-time job keeping the army's vehicles roadworthy because of constant patrolling, sand and dust.
Arriving and leaving al-Amara, in Maysan province, is a complicated process carried out under armed guard.
Passengers waiting to board a Hercules have to crouch by armoured vehicles, before being given the go-ahead to run on to the plane for immediate take off.
The question now is how long it will be before Iraqi security forces are ready to take over from the British.