Updated

In a rice field in northern Vietnam, 14 headstones are an enduring symbol of the wartime friendship of Vietnam and North Korea.

They mark the original burial ground of North Korean pilots who died while secretly fighting alongside Vietnamese comrades against U.S. Air Force and Navy planes during the Vietnam War.

The role of North Korea is a footnote in the sweeping history of that conflict, one that speaks mostly of the fraternal relations of two nations that separately fought bruising armed conflicts against the United States in the context of the Cold War.

Decades later, the communist nations' friendship is apparent as Vietnam gets ready to host a summit of the North Korean and U.S. leaders later this month.