Since these buildings are private, you can't enter, but when attending the races you remember looking up at their magnificent galleries overlooking the Circus Maximus. What wonderful views they offer to members of the imperial family! If you walk quietly and inconspicuously to the left, you may be able to view the fabulous sunken garden known as the "Hippodromus."
We know that this part of the palace complex was called the Domus Augustana (though it was built much later than the time of Augustus) because of an inscription found on two lead pipes:
Domus Augustanae, succura Euhodae Augusti liberti procuratoris
"Belonging to the Domus Augustana, under the care of the procurator Euhodes, freedman of Augustus" (Augustus is used here as a title for the reigning emperor, not for the man we call Augustus, first emperor of Rome)
For an example of such inscriptions, see this lead pipe bearing the name of the emperor Domitian, found in another part of the Palatine.
This model shows the relationship of the Domus Augustana to the more public part of Domitian's palace, the Domus Flavia, which you can visit by walking back to the Area Palatina.
Hippodromus