One of the more popular destinations in Laos is the southern Mekong islands known as the 4000 Islands. This is a little misleading as most of the islands are tiny and only a handful are inhabited. However the islands you can visit are a small rural villages well away from the larger cities of Pakse and Vientiane.
We were on a tour and arrived on the islands by bus on a ferry which was essentially a raft. It didn’t look safe, but heck, I can swim and you can see both banks on either side. Just don’t swallow the water if you end up in it.
Of note to see on these islands is the remains of the railway built by the French and the waterfalls – which were impassible and hence the failure of the railway system as there was no way through.
You can also visit the rare freshwater Irrawaddy dolphins – we didn’t do this as we didn’t have time but our guide said she’d been with a number of groups but not seen them so you really are taking a gamble if you choose to do this.