The excavations enrich our impression of the Roman city. They also provide the basis underlying the reconstructions and presentations in the Park and Museum.
The archaeologists' most important tool - a trowel - is never far away.
Colonia Ulpia Traiana is the only large Roman city north of the Alps that has not been extensively covered with new buildings since antiquity. Its remains are still only a few centimetres below the surface of the lawns in the APX and therefore readily accessible to researchers. This makes Xanten unique, for it is the only place where a complete Roman city can be investigated.
Visitors can view the excavations in the APX. They can take part in an open guided tour of an excavation site during the Roman Weekends. In addition, four "Live excavation" dates each year allow visitors to watch the archaeologists at work. Another possibility is to book a Guided tour of the excavations.
Excavations are presently under way on Insula 18 and Insula 34 in the APX.
Since 2005, the APX team has been excavating Insula 18 in a relatively untouched central part of the Colonia. The work revealed the remains of several walls of greywacke. In view of their enormous width, it was immediately clear that these must be the foundation walls of positively monumental Roman buildings. So far, however, it is totally unclear which large buildings might be involved.
The remains of graves dating back to the second half of the first century AD were found in the bottom layers. Since it was prohibited to bury the dead inside Roman settlements, these graves also give an indication of the western confines of the settlement before it became a Colonia.
Since 1998, educational excavations by the International Archaeological Summer Academy have been undertaken on the site of Insula 34. Every summer, thirty students from the whole of Europe excavate the remains of Roman homes inhabited by Roman craftsmen and their families.
The craftsmen's workshops were also located in the houses. Slag and molten residues indicate that a bronze foundry was located here. An underfloor heating found in the rear living area of the house suggests that this was a profitable business. This type of heating was a luxury that only the wealthy could afford.
Five wells were found in a large courtyard between the houses. Such wells are a real treasure trove for archaeologists, for the people in Roman times filled them with refuse from everyday life as soon as they ceased to be useful.
Several graves with objects dating back to the second quarter of the first century were found in the lowest layers under the courtyard. This small burial place was levelled only a few generations later. The Colonia's inhabitants were evidently not too pious to build their homes over the graves of their ancestors.
Excavations of the Roman residential neighbourhoods in insula 38 began in 2008. This is also where the guided tours of the APX excavations take place. The remains of a hearth and a great many Roman shards were found at the front, in the area facing the street. To the rear, however, there is no evidence of a building. This might have been the garden, maybe with small stables.