We walked down to the Circus Maximus, and on the way we noticed the odd Roman legion wandering around.
It turned out there was a re-enactment going on, so when we reached the Circus we saw patricians and lots of soldiers.
The Circus Maximus was the first – and largest – chariot racing stadium in Rome, apparently set up by the Etruscan kings of Rome. In its heyday it could seat up to 400,000 people to watch the chariot racing; the last recorded use was AD 549.
In the centre, there’s the spina (raised area to separate the tracks - that's the wider green bit between the two worn bits below) and various statues and obelisks were set upon it.
Then we went to the church of Santa Maria in Cosmedin.
The church has the Bocca della Verità in its porch – this is the face of the sea god Oceanus, used by the Romans as a drain cover but in medieval times you put your hand in its mouth to show that you were telling the truth (liars' hands would be swallowed).
Inside, the church is beautiful. Apparently the altar is a pink Roman bathtub, but there was a service going on (with gorgeous singing) so we didn't want to disturb anyone.
So we went into the sacristy to see the 8th-century mosaic of the Adoration of the Magi from the original Greek church on the site.
The temple of Vesta opposite the church dates from the 2nd century BC. It's actually the Temple of Hercules Victor, and is the oldest surviving marble structure in Rome. This area of the city used to be the cattle market, aka the Forum Boarium.