If, like me, you are not planning to come back to Laos, you should try to see the Plain of Jars. To get there from Luang Prabang, I hired a car and driver, which cost a fortune, but it meant that I had the freedom to go where I liked, and the trip did not take quite as long as it would on a public bus or minivan. Still, the journey is a long one - 7 hours (one way) on a bumpy, winding road through mountain villages. You can see Site 1, the biggest and most popular, when you arrive in Phonsavan; stay overnight somewhere (I can't recommend the 'resort' I stayed in, sorry), and then you can see Sites 2 and 3 the next morning before the return journey. The stone 'jars' are amazing. It was well worth the effort...and the expense.