Relaxing — deep, immediate muscle release.
Rich in active gases or metals — a strong mineral character.
Dense, salty water — you float without effort.
Aachen is the most historically resonant thermal city in northern Europe, its chloride-rich hot springs — among the hottest naturally occurring in continental Europe at up to 74°C — having drawn Charlemagne himself to establish his Carolingian capital here in the 8th century and bathe daily in the thermal waters he so prized that he invited his entire court to share them. The Kaisertherme (Emperor's Baths) continue this imperial thermal tradition in a city where the legendary Carolingian Cathedral — a UNESCO World Heritage Site containing Charlemagne's throne and golden reliquary shrine — still stands at the center of a living spa culture, and where thermal bath establishments are embedded within the medieval city center as they have been since the 1st century AD. The naturally heated chloride and sulfate springs, known for their very high mineral concentration and temperature, are recommended for rheumatic, dermatological, and circulatory conditions, and Aachen is recognized as part of the UNESCO Great Spa Towns of Europe alongside Bath, Bad Ems, and Vichy. Few spa experiences in the world carry the weight of 1,200 years of continuous royal bathing history that Aachen's extraordinary hot springs represent in the heart of Europe.