Archaeologists Find Ancient Roman Luxury Baths With Underfloor Heating

Archaeologists uncovered an ancient bath complex below the streets of a German city dating back to the Roman Empire.

The discovery came during the construction of a new fountain in Neumarkt, located at the heart of Cologne—a city in the west of the country whose history stretches back around 2,000 years.

In 50 A.D., the Romans founded a colony on the Rhine River that would eventually develop into the Cologne of today. Numerous remains from the ancient Roman settlement, known as Colonia Claudia Ara Agrippinensium, can still be found in the modern settlement. A private Roman bathing facility can now be added to the list, German news outlet T-Online reported.

The luxury bathing facility once formed part of a residential building that featured sophisticated furnishings, Gregor Wagner, an archaeologist with the city's Roman-Germanic Museum and head of the excavations, told local newspaper Kölnische Rundschau.

The affluent nature of the residence could be determined, among other things, by the existence of painted plaster on the walls.

Green marble from Greece was used in the ancient bath facility, which also features an underfloor heating system, Kölnische Rundschau reported. The heating system would have involved the use of heated air to warm the floor from below. The floor itself would have been supported by pillars.

The facility featured different baths that would have been filled with hot, lukewarm and cold water, respectively. As evidenced by other bathing sites, the Romans apparently understood the potential health benefits of alternating between hot and cold temperatures.

Researchers also found a room at the facility where a boiler would have been located and used to produce warm air for the underfloor heating system, as well as hot water for some of the baths. The bath complex was likely added to the residence after it was constructed, Wagner said. It is possible that it was originally a living space and was later converted.

"It's a small sensation that we found this here," Wagner told Kölnische Rundschau.

The bathing facility has been dated to the late 4th century, based on the Greek marble and other artifacts found at the site, such as ceramics and Roman coins.

The private bath complex is the fourth to be found in Cologne to date, although Wagner suspects more exist that have yet to be found. In Roman times, the Neumarkt area was the site of an ancient city district.

Just last month, a "huge" bathing facility from the Roman era was discovered in the Spanish city of Mérida in "excellent" condition.