They named it the Great Wall of Vietnam. Above it they could make out an open space and traces of light, but they had no idea what lay on the other side. A year later, they have returned—seven ...

The Passchendaele Passage is home to a 300-foot (90 m) wall of calcite known as the Great Wall of Vietnam, which cave ...

At the end of Hang Son Doong stood the Great Wall of Vietnam, a 200-foot barrier to be conquered by both ladder and rope climbing. In a cave there’s no way to get a signal. There’s no way to ...

The wall honors over 3 million Americans who served in the U.S. Armed Forces during the Vietnam War and bears the names of ...