Twenty kilometres east of Sepon, Ban Dong (Dong Village) was on one of the major thoroughfares of the Ho Chi Minh Trail, and was the site of the only Lao–Vietnamese military collaboration during the war. Most of what was previously scattered around the area has been gathered into the gated front lawn of the so-called War Museum (the official name is 'Museum of Lao-Vietnam Legacy of Joined Victory Battle on the Road 9 Area').
These include two American-built tanks used during Operation Lam Son 719, a disastrous Army of the Republic of Vietnam (ARVN) assault on the Ho Chi Minh Trail in February 1971. Despite support from US combat aircraft, the ARVN troops retreated across the border at Lao Bao after being routed by seasoned North Vietnamese Army (NVA) troops at Ban Dong. To see the tanks, part of a plane, guns and other scrap, as well as photos and displays, the museum is at the eastern edge of Ban Dong and is bordered by a baby-blue-and-pink fence.
The dirt road that borders the War Museum was one of the main branches of the Ho Chi Minh Trail, and is today one of the most accessible points. Elsewhere you'll need a guide.
