In the past, archeological excavation was devoted eminently to the recovery of objects with artistic value, while topographical research was limited only to the recovery of important architectural structures.

Today, rather, archeological research represents an intense activity of documenting every detail left behind by the action of man.

The formation of archeological deposits is subject to the same laws of geology, but is complicated by the intervention of man. Therefore, the archeologist not only documents the factors of erosion, but also the accumulation and removal based on the activity of man.

Signs of man's intervention are recognizable by pits or holes (factors of removal), or by horizontal, vertical, or layer deposit formations, or walls (factors of accumulation).

All of these elements compose a "stratigraphical unity" that are numbered progressively during excavation. They are then surveyed and positioned on a map and can therefore be laid out according to the inverse layer formation (from the most recent to the most antique).

This methodology involves the management of enormous data, especially in excavations of extensive urban areas that need to be organized in chronological order.
For this purpose, an elaborate system was used in England during the 1970's, taking the name of its inventor and defined as "Harris' Matrix".
The system is able to confront even the most complicated stratigraphical sequences. The chronological sequence is based on the comparison between the most recent stratigraphy with the oldest, and with the oldest of the most recent..

> It is possible to see some excavation images from the Forum of Nerva

> Forum of Augustus

> Forum of Caesar

> Forum of Nerva

> Temple of Peace

> Forum of Trajan

> Trajan's Market

> Presentation of the operation

> Methodology of the archeological excavation

> News from the Forum workshop

> The staff engaged in recovery