Named for Publius Aelius Hadrianus (76–138), Roman emperor, who was adopted by Trajan {see planet  (7445)} and who became his successor in 117. Hadrian stopped the expansion of the Roman empire, putting his energy instead into the construction of excellent roads, aquaducts and new cities. He also fortified the borders of the immense empire, notably with the wall between England and Scotland and the limes in Germany. He reformed the economy, administration and the law. An admirer of Greek culture, Hadrian built the Castello de Sant’ Angelo in Rome. (M 30802) _ _.