Dinocrates did not leave the king, but followed him into Egypt. There Alexander, observing a harbor rendered safe by nature, an excellent center for trade, cornfields throughout all Egypt, and the great usefulness of the mighty river Nile, ordered him to build the city of Alexandria, named after the king. This was how Dinocrates, recommended only by his good looks and dignified carriage, came to be so famous.

Introduction, Sec. 4 - De architectura (The Ten Books On Architecture) (~ 15BC) - Book II