The existence of this apparently “splendid” villa means that there was a time, back when the Romans lived in England, when there were a greater number of rich and powerful people who built grand houses to show off their power and wealth. Now, however, the villa is in ruins and covered in plants, which means that it has been a really long time since the days of these grand families. This harkens back to when the narrator describes how hard it would be for a traveler to find a castle. Furthermore, this villa and its condition brings up the question of
why the Romans left and provides evidence of past turmoil.