Site 1, ten kilometres south-west of Phonsavan, is the largest and most accessible of the jar sites: more than 300 stone jars scattered across a grassy hillside with a backdrop of forested ridges. Many of them have toppled over, some are broken, and a small handful still wear stone lids. The single largest — Hai Cheuam — stands three metres tall.
Walk the marked paths only. The white MAG-laid markers indicate cleared ground; the red markers indicate uncleared ground still seeded with American cluster bomblets. A small cave at the back of the site has a hole in the roof which the bombing campaign opened up; locals took shelter here during the worst of the raids in the late 1960s.