Savannakhet is the second-largest city in Laos and the capital of its most populous province. Sitting on the Mekong opposite the Thai town of Mukdahan, it has a sleepy charm with crumbling French colonial buildings in its old quarter, a handful of Chinese shophouses, and a Vietnamese-influenced Mahayana Buddhist temple alongside the usual Lao wats.
The city is mainly a transit point for travelers crossing between Thailand and Vietnam -- the east-west corridor runs through here to the Vietnamese border at Lao Bao. But it is worth a night if you are passing through. The old town is pleasant for a wander, the riverside is attractive at sunset, and the Dinosaur Museum on the outskirts displays fossils found in the province.
The surrounding countryside has some interesting destinations. The Heuan Hin stone formation (sometimes called the Lao Stonehenge) and the That Ing Hang stupa, one of the most revered in southern Laos, are both within easy reach. The Ho Chi Minh Trail ran through Savannakhet Province, and UXO clearance continues in the area.