Pak Beng lies at the halfway point along the Mekong River between Huay Xai and Luang Prabang. It is a popular drop off point for passenger ferries and has one of the most developed tourist infrastructures in the area.
There are a number of restaurants and guest houses in the town and there is even a constant supply of electricity, unlike other towns nearby. The streets leading to the pier are lined with street stalls, shops and restaurants. For something more authentic however, head to the local market in the town center, which starts at sunrise. Here you will find a variety of local cuisine as well as some questionable products.
The surrounding countryside is worth exploring, although be sure to take all of your belongings with you and leave nothing of value in your hotel room. The river is another source of attraction, with beautiful riverside walks and water sports available.
The most common way to reach Pak Beng is by river. There are boats available to and from all of the towns along the river including Luang Prabang. The slow boat takes two days to cover nearly 200 miles so make sure you have plenty of time available. There is a small gravel road leading to Udomxai, but no buses available.