Which is an improvement king darius made to his empire?

An improvement King Darius made to his empire is the creation roads. Daríus I the Great worked to restore order in the empire, carried out an administrative reform and implemented a type of monetary economy that encouraged the development of local commerce. At the same time it restructured the Empire dividing it into twenty administrative and legal units. He was the one who indicated that roads were built that united his city with all the administrative units; He also created an efficient postal system, in addition to promoting again the belief in Persian religion with protection to local cults.

He then graduated to full-blown espionage in the summer of 1781, when he infiltrated Charles Cornwallis's camp by posing as a runaway slave loyal to the British. He proved so convincing in the undercover role, that Cornwallis eventually enlisted him to work as a British spy

Explanation:

Cornwallis surrendered October 19, 1781