Since some years archeologists are at work on the slopes of the palatine hill near the arch of Constantine along the side of the sacred road. 

The archaeological excavations are directed by the University La Sapienza Professor Clementina Panella.
Every coliseum’s visitors moving toward the arch of Titus and the roman forum can see the excavations and the many students involved in the diggings

The form of the splendid and famous Piazza Navona is derived from the Stadium of Domitian. Some scholars believe it was the most elegant place for shows of the ancient world . The stadium was the first sport’s building built in Rome to house the gymnastic competitions : running, wrestling, boxing. 

The early Christian community took care of the burials of their members. Because of shortage and expensive price of the land  (nothing changed in the past 2000 years ) they created  underground cemeteries excavating tunnels in the volcanic rock  where the bodies were placed in niches along the corridors and sealed with clay or marble slabs. 
Each tomb had the name of the deceased and was also decorated with simple but meaningful symbols. The most common Christian symbols used in the catacombs are:

THE FISH : in Greek fish is written  ICHTHYS:  each Greek letter is the initial  of the words : Jesus Christ Son of God Savior.

     I- stands for IESOUS - (Jesus)

     CH- stands for CHRISTOS - (Christ)

     TH- THEOU stands for - ( of God)

     Y stands for UIOS - ( Son )

     S- stands for SOTER - (Salvatore )

- The MONOGRAM OF CHRIST: it is composed of two Greek letters of the alphabet , X ( chi) and P (ro), woven together . They are the first two letters of the Greek word Xristos , that means Christ . -

- The ANCHOR: meaning  the hope in the promise of a  future life .

- A DOVE with an olive branch in its beak : a symbol recalling the  salvation of Noah after the flood.  Consequently it symbolizes the idea of the soul in a heavenly peace