The Plain of Jars is an archaeological wonderland. Throughout the region are hundreds of enormous stone jars thought to be used for burials. The jars are believed to have been created during the iron age, around 2000-2500 years ago. Their origins and purpose are still unknown as there are no markings or other remains to give us any clues. There are 90 jar sites in total, each containing between 1 and 400 jars. The best place to visit the jar sites from is Phonsavan, the regional hub. Many of the jar sites are damaged from US bombing runs during the Vietnam War. Sadly many of the sites are still regarded as dangerous, due to unexploded bombs scattered throughout the region, so take care when exploring them. You will most likely require a guide to transport you between sites and to tell you which areas are safe and which are not. These jars are an incredible piece of history and are part of a major archaeological mystery and should definitely be seen by everyone.