What are the three significant accomplishments of the Mauryan rulers?

So first off, Chandragupta created a bureaucratic government. He divided the empire into four provinces with a prince ruling in each province, with local districts run in each province. Chandragupta created the capital of the empire with gold pillars, fountains, and beautiful parks. Asoka had extensive roads built that reached the far corners of India with a house and well set up as a rest stop every nine miles.