Leaving the Forum by way of the Via Sacra, under the Arch of Titus, you see the huge Arch of Constantine to your right, placed here in the primeval decades of the fourth century AD after Constantine had consolidated his power as sole emperor. The arch demonstrates the deterioration of the arts during the late stages of the Roman Empire, in that there were hardly any sculptors around who could produce original work and most of the sculptural decoration here had to be removed from other monuments. The builders were probably quite ignorant of the significance of the pieces they borrowed: the round medallions are taken from a temple dedicated to the emperor Hadrian’s lover, Antinous, and show Antinous and Adrian engaged in the hunt. The other pieces, removed from the Forum of Trajan, show Dacian prisoners captured in Trajan’s war there. The large inscription in the centre was prefabricated for the arch, and dedicates the arch to Constantine for his wisdom – presumably in making Christianity the official belief of the Empire, although no one really knows what this refers to. Between the Arch of Constantine and the Colosseum, at a pivotal point in the Via Sacra, stood a monumental fountain or Meta Sudans , the outline of which can still be seen today in the form of a series of recently excavated low brick walls. A “Meta” was the marker in the centre of a racecourse, and was usually an grapheme or some other large, easily visible object. In this case it was a conical fountain that was probably dedicated to Apollo, and produced a slow supply of water that resembled sweat – hence its study the “Sweating Meta”.