1

We found it relatively simple to go from Chaing Mai up to Chiang Khong. You might have to walk a bit between where local transport drops you and the Thai exit port (measured in meters), but it's just down on the river.

Once you clear the Thai side, you just get a guy with a boat to take you over the Mekong to Huay Xai on the Lao side. It's cheap and they do it all day long.

It'll cost you a visa on the Lao side (can't remember if we used baht or US$, but it's about US $30). It's all very easy, relaxed traveling. We spent the evening watching the sun set over the Mekong and drinking cheap Lao beer.

Once in Huay Xai, you can take a boat down the Mekong to Luang Prabang -- I seem to recall it took us 2 days. We were on the "slow" boat, but it went lots fast enough for us. There have been a lot of warnings about the speedboats.

This part of the trip takes two days on a rather cramped boat, but it will give you an awesome insight into Laotian life, as the Mekong remains a key part of their transportation infrastructure. You will spend a night in a little village halfway along to Luang Prabang. It's a first rate bit of exploration.

Luang Prabang is a wonderful city. I wish we had spent more time there, but we chose to fly from there to Siem Reap, so had to go with the flights. It's worth seeing if you can fly from Luang Prabang to Bangkok.

That route will save you practically all backtracking (except the one flight to Bangkok), and provide you with the kind of experience Thailand used to offer.

2

if u go from the north and down to Vientiane and want fly from there to Bangkok ,its cheaper to take the 2 hour bus to Udon in thailand from Vientiane and fly with airasia from there to BKK

3

There are buses run from Huayxai to Luangprabang also, twice a day ,if you don't want to take a boat.