BRUMONT (Italy) • Frescoed barracks which once housed the cavalry of Emperor Hadrian's bodyguard have returned to light 19 centuries on, during excavations for a new underground train line in Rome.

In a find hailed as "unique" by archaeologists, weapons rooms, dormitories, kitchens and stables where some of ancient Rome's crack troops once lodged now lie open to the sky near the Colosseum, where the Amba Aradam stop of the Metro C line is being dug.

Uncovering broken pots, Roman coins or that archaeological staple, a series of low walls, is all in a day's work for head engineer Andrea Sciotti, particularly near the ancient forums and gladiator battling ground and training schools.

"But this time, the effect was different. The emotion crept up upon us," he told AFP over the noise of concrete-mixers and drills, marvelling at the excellent state of preservation of the vast site, which covers 900 sq m.

Amid the diggers and scaffolding lie the remains of 39 rooms of barracks where hundreds of soldiers - the so-called "equites singulares augusti", one of the elite corps of the Praetorian Guard - were housed during the second century AD.

AGENCE FRANCE-PRESSE