The city contains the ruins of two large Roman bathhouses, the Kaiserthermen that sits adjacent to a major traffic circle, and the Barbara therme closer to the river. These ruins are extensive, giving the visitor a good picture of the complexity of the structures.
In Roman times, the spacious and richly ornamented building of the 'Barbara' Bath stood close to the bridge over the Moselle which is a short walk from the Basilica of St. Matthias. These public baths, built in 150 AD are considerably older than the Imperial Baths, and were the second largest public bath in the Roman Empire ,second only to Trajan's baths in Rome. The walls of the bath were not built as high as the others. Mainly because the old walls, as those of the Amphitheatre, served as a conveniently situated quarry until the 17th century, making was remained not so impressive as those of the Imperial Baths.
Their name of 'Barbara Thermae' actually derives from the suburb of St. Barbara, later on built on part of the old site. The term thermae was the word the Ancient Romans used for the buildings housing their public baths.
An impressive and convincing proof of the skill of urban architecture of that period, these baths were built near the bridge across the Moselle at the western end of the town's Roman Main Street, leading eastwards - from the Moselle bridge to the Imperial Baths and then to the Amphitheatre. Later on, during the Middle Ages, this same street with its walls, towers (Red Tower) and gates ('Neutor') became the town's southern boundary. This is today the Südallee and Kaiserstrase.
Allthough its at the time of writing under construction, and is not that imposing as the Kaisers thermen the St. Barabara baths has been in historical perspective moore important than the former ones because it has been in use for a considerable longer period. Its been build in the 2 th century and it is a hughe construction. There are moore rooms than the Kaiserbaths contains and a lot more tunnels. It displays coldwaterbaths, warmwaterbaths, a gym, and a stoa.
Trier has two sets of Roman baths, the St Barbara Baths and the Imperial Baths. The first is the older of the two, dating to about 150 AD. They once had an extensive network of hot and cold baths, a large swimming pool, and changing rooms, all heated by an elaborate under-floor system called the hypocaustum This was the biggest bath complex of the Roman world. Sadly, after centuries of use, they were abandoned and much of the material taken for other uses.
The Imperial Baths date to the rule of the Emperor Constantine in the 4th century AD. They once formed part of the city walls, but were never used for their intended purpose.
These Roman baths date from the 2nd century, probably because the smaller baths in the Viehmarkt could no longer meet the needs of the growing population. The Barbarathermen were in use to the end of the 4th century and are much larger than the Viehmarktthermen. They lie just outside the line of the Medieval city walls and the site was, in fact, used as a 'castle' during Medieval times.
The scavenging of stone over the centuries, plus the construction of the 'castle' an, later, a Jesuit college, means that only the foundations and underground structures of the baths remain. Only a third of the site has been excavated and, from what I could see, it was a huge complex.
Although there were once guided tours through the underground passages and areas of the baths the site has been closed for restoration since 2000 (and, I suspect, for dealing with safety issues). I'm not aware of any date for re-opening but, from the many tools left lying around the site, it is clear that they are still working on it.
You can get quite a good view of the Barbarathermen from the roadside: the surrounding wall is low. If nothing else, you can get an idea of just how huge these baths were before walking along Kaiserstrasse/Sudallee to find the even larger Kaiserthermen.
The Barbar-thermen (or Barbara Baths), located near Trier's Roman Bridge, are the third largest baths ever created in the Roman Empire. Originally built in the 100s AD, the baths measure 240 meters by 172 meters. After the fall of the Roman empire, the baths became a castle-fortress. Later they were torn down for their stone, which was valuable for construction.
Today, all that remains are undersground sections, such as the heating tunnels. Parts of the Barbara Baths have yet to be explored.
The extensive ruins were used as a castle in the Middle Ages, then torn down and recycled as building material until the remains were used for constructing the Jesuit College in 1610.
Only the foundations and the subterranean service tunnels have survived, but the technical details of the sewer systems, the furnaces, the pools, and the heating system can be studied better than in the other two baths.
The Barbarathermen (Barbara Baths) were built in the second century AD. It was then the second largest Roman baths after the Trajanus Baths in Rome (built between 104 and 109). The baths got its name after a not any longer existing monastery at the place.
This far only a third of the facility has been excavated but it is still very impressing.
The ruins were used as a castle in the Middle Ages, then torn down and recycled as building material until the remains were used for constructing the Jesuit College in 1610.
Due to the excavations works are the baths closed for visitors but one can look over the fence.