Since I don't have a twitter...purpose of the roads

Roman Roads: the purpose of the roman roads was to move their armies and trade products as well as communicate.
Persian roads: the royal road was built to facilitate fast communication throughout the large empire.
Incan roads: quick and reliable routes for civilian/military connections on foot. Purpose to boost communication, also aided caravans.

I think the roman roads were the best because they took the initial developments of the Incan roads and improved them for the better.