The Thermal Spring is the most beautiful, hottest and most popular spring in Karlovy Vary, the dominant of the main Colonnade and everyday stop of walks in the enchanting valley of the Teplá River. Its water reaches the temperature of 73.4°C. It spouts under strong pressure of carbon oxide from the very heart of the earth located thousands of meters deep underground up to the amazing height of 12 metres. The history of its translucent water, known also under the Mattoni or Aquila brands, is 300 thousand years old.
The Thermal Spring, in the past called Brudel, Sprudel or Fous, which is able to release up to 2,000 litres of hot mineral water every minute, is undoubtedly the most frequently visited thermal spring of all fifteen springs in Karlovy Vary. The geyser of hot water rises on the Thermal Spring Colonnade, whose image has been influenced by changeable period fashions since the 16th century. The original Baroque building was reconstructed several times - through the Empire style, provisional wooden colonnade, till getting its current shape - an interesting architectonic concept dating back to the 60s of the last century, when the Thermal Spring shows its magnificent power inside a glass dome, protecting this romantic fountain.
The Thermal Spring is a rich source of mineral substances and necessary trace elements, its use for medical treatment is quite large. Apart from the drinking cure within which thermal water 41-72°C hot is drunk, the Thermal Spring is also used for baths. The extraordinary effects of the spring on the human organism were known in ancient times, but the oldest preserved records glorifying the Thermal Spring refer to baths of King Charles IV and date back to the end of the 14th century. It was decades later that doctor Becher managed to determine the ideal form and manner of the internal use of thermal springs, tailored to the individual need of patients. The golden age of the spa business in Karlovy Vary, connected mainly with the Thermal Spring, came around in the 18th century, and later, in a more advanced form, it has continued up to now.
Thermal water, which is unique in its chemical composition and physical properties, does not only rise on the Thermal Spring Colonnade where visitors drink it in traditional spa porcelain cups. Thanks to a unique underground piping it is available, free of charge, to all guests of the Carlsbad Plaza hotel as well. They may fill a cup of the mineral water directly in the hall next to the main reception.