28km (17 miles) SE of Liège
To uncover the origin of mineral springs, you need to go straight to the source. Where better to begin than Spa? The town (pop. 11,000) virtually floats on some of the healthiest H2O ever to gurgle up to the surface and has been a bustling resort ever since a medieval blacksmith from other parts bought up the land holding these wondrous springs (the Roman geographer Pliny the Elder, in the 1st c. A.D., might have been referring to these waters when he wrote about a curative spring in the country of the Tungri). The town that grew up around them has catered to the likes of Charles II of England, Montaigne, the queen of Sweden, and Czar Peter the Great of Russia. So universally was its name equated with the miracles of thermal springs and mineral waters that the word "spa" is now applied to health and fitness centers of every description.
In the 18th and 19th centuries, curistes came from all over Europe to take the waters, gamble their money in the casino founded in 1763 (and said to be the world's oldest) and, like Victor Hugo, stroll the forested Promenade des Artistes just outside town. Nowadays, visitors pour in for the Formula One motor race at the nearby Spa-Francorchamps circuit, arguably the most scenic racetrack in the world.