A prisoner-of-war camp is a site for the containment of combatants captured by their enemy in time of war. It is similar to an internment camp which is used for civilian populations. The first recorded use of a purpose built prisoner-of-war camp was during the Napoleonic Wars[citation needed] and they have been in use in all the main conflicts of the last 200 years. In the main camps are used for soldiers, sailors, and more recently, air crew who have been captured by an enemy power during or immediately after an armed conflict. In addition, non-combatant enemy personnel, such as merchant mariners and civil aircrews, have been imprisoned in some conflicts.[citation needed] With the adoption of the Geneva Convention on the Prisoners of War in 1929, prisoner of war camps have been required t