At its peak around the second century AD, the Roman Empire spread across more than five million square kilometres. Using modern geography, the empire went from Spain and Morocco in the west to Iran in the east. It went from the United Kingdom in the north to Egypt in the south. Look at a map of Europe and North Africa and then imagine most of it covered by the Romans.
Controlling such a huge area was a difficult task and, as historians know, eventually it became too hard and the empire began to break apart. But there were many centuries when the power of the Senate, the Emperor and the associated bureaucracy successfully governed their land from Rome. At the centre of it all was the Roman Forum.
See more photos on my blog: https://www.timetravelturtle.com/roman-forum-palatine-hill-rome-italy/