Now walk to the other end of the Rostra 0=====x, so at one end was the Umbilicus o= and at this end was the MILLIARIUM AUREUM =x (sometimes spelled with one L).
As you walk by the flowing modern water spigot, take a drink, the water is fine :-) . This water comes from the springs in the very same area that the Aqueduct Marcia once ran its 91 km course to supply Rome. The water from this aqueduct was said to be the coldest and the best tasting of all the aqueduct waters in ancient times. Oh yea, the key to drinking from this spigot is to block the water flow with your finger. There is a small hole on the top of the spigot that will now send water squirting out and up like a regular drinking fountain. Ok now at this end of the Rostra there is no 'Milliarium Aureum' to be found? But turn around and look at the Temple of Saturn. Across the street that you are standing on there is a fence and on the grass just behind the fence on stone rubble there is a large slightly curved marble fragment.
With a marble plaque below it saying 'Millairivm Avrevm'. The second 'Millairivm Avrevm' fragment is just to the left of it (1 m) and is a short round marble column stump with a lot of holes in it. (marble shaft; 1.42 m long and 1.17 m diameter, two sides left rough and traces of bronze facing(?). The other piece is a section of a circular marble plinth decorated with palmettes=palm leaves). This according to ancient writers descriptions is roughly its exact location (these pieces were found nearby and placed there).
Milliarium Aureum means 'Golden Milestone'. Romans placed simple 'Stone Milestones' on their roads every 'Roman Mile' to mark distances just like we sometimes do today on our highways. 'Golden' was because it was covered in bronze. Engraved on this Golden Milestone were the major cities in the Empire and their distances from Rome (some say on bronze plaques). But this Golden Milestone was just symbolic and a fancy showpiece. See the real starting points (or zero) for measuring the road distances began at whatever of the 37 Servian Wall City Gates a road actually left Rome from. Think of those old war movies or MASH (movie and TV series) where the soldiers for fun put up a wooden post with arrow signs =====> reading 'CHIGAGO 6287 mi'.
Emperor Augustus erected this monument in 20 B.C. when he became the 'Cura Viarum' or Superintendent the Roman road system :-) . Above is what guidebooks and guides will say about this site and of course throw in the "All Roads Lead To Rome" phrase :-) . But this is probably more closer to the truth. The location you see today is very likely roughly where it was moved to decades later when the 'Schola Xantha' was built at this end of the Rostra.
Its original location when erected by Augustus was very probably at the end of the Rostra o=====x.
In 1959, H. Kähler found a round concrete base at this end of the Rostra.
This was very likely a base for a single column-like structure. The two pieces we see today labeled 'Millairivm Avrevm' were found in this general area (exact location not recorded I believe) in an 1830's excavation before a road was built. And *believed* then to be part of the Golden Milestone. That large section with the palm leaves is far too big to be part of a column-like monument unless it was *huge*. It's something that would be placed *on top* of a structure or building. And guess what? Its diameter is exactly the same as the top of the Umbilicus at the other end of the Rostra! And that is very likely exactly what it was.
The column section of the Golden Milestone is probably iffy also. It's believed that the Golden Milestone was is the actual rectangular  shape of a milestone and not a circular O column. Which makes a lot of sense when you think about, it is a milestone after all. Who knows *perhaps* that column section was on top of the Umbilicus also? It's believed it had either a statue or column on top? And there is no proof that the Golden Milestone had any MASH-like signs or engravings on it listing a city and its distance from Rome. One hint from Cassius Dio is that the Golden Milestone just listed the name of the Road and the 'Curatores Viarum' or the man appointed by the Emperor in charge of its upkeep.
This is a good vantage point for 'The year of the Four Emperors' (68-69 AD).
You see General Otho met his Praetorian conspirators at the Milliarium Aureum when he betrayed (with good reason) Emperor Galba and was spirited away to their barracks.
Emperor Galba was later attacked and killed within 50 m of you (more later) and Otho became Emperor.
He lasted three months and when defeat was imminent by General Vitellius he honorably stabs himself in the chest.
Vitellius becomes Emperor but has General Vespasian troops marching on Rome. Vespasian's son Domitian (later Emperor) is hiding on the Capitoline Hill and later sneaks away disguised right by were you are standing. Vitellius is later murdered on the stairs behind the Arch of Septimius Severus as I mentioned earlier. And General Vespasian becomes Emperor and builds the Flavian Amphitheatre (Colosseum).
For more information and photos, please see Milliarium Aureum in A Tourist in Rome.Next: #12.1: Tabularium