Baden-Baden (German pronunciation: [ˈbaːdn̩ ˈbaːdn̩] ⓘ) is a spa town in the state of Baden-Württemberg, south-western Germany, at the north-western border of the Black Forest mountain range on the small river Oos, ten kilometres (six miles) east of the Rhine, the border with France, and forty kilometres (twenty-five miles) north-east of Strasbourg, France.

The springs at Baden-Baden were known to the Romans as Aquae ("The Waters")[4] and Aurelia Aquensis ("Aurelia-of-the-Waters") after M. Aurelius Severus Alexander Augustus.

The highest mountain of Baden-Baden is the Badener Höhe (1,002.5 m above sea level (NHN)[12]), which is part of the Black Forest National Park.

[10] The water is rich in salt and flows from artesian wells 1,800 m (5,900 ft) under Florentine Hill[13] at a rate of 341 litres (90 gallons) per minute and is conveyed through pipes to the town's baths.

[5] The known ruins of the Roman bath were rediscovered just below the New Castle in 1847[5] and date to the reign of Caracalla (AD 210s),[11] who visited the area to relieve his arthritic aches.

The Baden-Baden witch trials, an investigating encompassing the entire territory and resulting in hundreds of verdicts, took place in 1627-1631.

[11] The margravine Sibylla rebuilt the New Castle in 1697, but the margrave Louis William removed his seat to Rastatt in 1706.

[11] The town was frequented during the Second Congress of Rastatt in 1797–99[citation needed] and became popular after the visit of the Prussian queen in the early 19th century.

[11] She came for medicinal reasons, as the waters were recommended for gout, rheumatism, paralysis, neuralgia, skin disorders, and stones.

[citation needed] Reaching its zenith under Napoleon III in the 1850s and '60s, Baden became "Europe's summer capital".

[11] With a population of around 10 000, the town's size could quadruple during the tourist season, with the French, British, Russians, and Americans all well represented.

)[15] The theater was completed in 1861[10] and a Greek church with a gilt dome was erected on the Michaelsberg in 1863 to serve as the tomb of the teenage son of the prince of Moldavia Mihail Sturdza after he died during a family vacation.

[19] Lichtenthal, a residential area in the southwest of the town, was hit by bombs and Saint Bonifatius Church was severely damaged on 11 March 1943.

On 2 January 1945 the railway station of Oos and various barracks on Schwarzwald Road were heavily damaged by bombs.

CFB Baden-Soellingen, a military airfield built in the 1950s in the Upper Rhine Plain, 10 km (6 mi) west of downtown Baden-Baden, was converted into a civil airport in the 1990s.

[28] Sights include: The main road link is autobahn A5 between Basel and Frankfurt via Freiburg, Karlsruhe and Mannheim, which is 10 km away from the inner city.