sentences:  He wished to know where the "Indus (which is the only river save one that produces crocodiles) emptied itself into the sea".After personally leading his elite forces, whose ranks were restricted to those with Persian, Mede, or Elamite ancestry, to fight the invading Scythians, he led a campaign of conquest towards South Asia, conquering Sindh in 519 BC and constituting it as his 20th satrapy.After the fall of the Achaemenid Empire, Alexander the Great also crossed Maka in his campaign of conquest.