It was not abandoned wholesale, as many think. The Flavian emperors who came to power after Nero's death in 69 had listened to public opinion, and the Roman public was not very happy with Nero's capricious building program. We get scattered reference to the building as "hated." Tacitus (Annales 15.52) makes a character say that the best place to murder Nero was in illa invisa et spoliis civium exstructa domo ("in that house, hated and erected from the plunder of the citizens"). Vespasian immediately drained the great lake Nero had created and started construction of the Amphitheater on its spot, thus opening up the whole area to foot traffic again (Nero's park had been like a blood clot as far as circulation in the city). A lot of the art which had been in the Domus was rededicated in the Temple of Peace. But the main structure of the Domus survived Nero's death, and was apparently still in use, though probably on a smaller scale. We find a lot of Neronian-era brickwork that survives intact with evidence of re-use all the way up to 104 CE. Vespasian's son Titus built his Baths nearby, but not on top of the Domus, and Pliny the Elder visited the Domus and saw artwork there in 79 (NH 36.37, famously). A major fire on the Palatine in 81 CE seems to have destroyed a lot, because we hear about Domitian being obsessed with the restoration. Trajan was still trying to finish Domitian's plans for the restoration when another fire, in 104, ended the building for good. It was at this point that Trajan decided to put baths on top of the whole structure. We find a lot of evidence of architectural efforts to turn the Domus into a reinforced substructure, with most of the rooms filled with rubble to provide a solid foundation. The reason for this was probably expediency: the Domus had been massive, and its ruins were easier used as a base than cleared away to start from scratch. This act preserved the Golden House for posterity, because the sealing off of the rooms and the filling of the cavities with rubble fill protected the substructure from the elements and especially moisture. There were little entrances into the Domus ruins beneath Trajan's Baths for centuries, probably back into the medieval period, and we know that many Renaissance painters descended into the grottos for inspiration (and hence the Italian term grotesque).