The ancient Roman Empire was the largest empire of the world, at its peak the greatest territorial extent of the empire was almost 2 million square miles with a population from 50 to 90 million people. From the 1st century Romans created settlements along the Danube river to protect the empire from the east. There were several settlements created in the actual territories of Hungary, some ruins can be seen in the Northern part of Buda even today.
You can visit the ruins of an amphitheatre or Aquincum, the centre of the settlement with the remains of the governor’s palace and many residential buildings.