Hadrian began his reign by abandoning Trajan's eastern conquests. In 121 AD, he embarked on the first series of journeys which took him to practically every corner of the empire.
His major concern was the security of the frontiers. He strengthened the defences in several areas including the Rhine and Danube. His most famous construction is The Hadrian Wall in northern England, built to divide the Romanized Britons from the barbarians.
Hadrian loved Greek culture and he travelled to Greece and the Helenized eastern provinces. He spent three winters in Athens. He donated a library, forum, and arch to the city. Hadrian also went to Egypt, to the Nile and Thebes. He planned to refound Jerusalem as the Roman city of Aelia Capitolina which sparked the Jews revolt.