send owls to Athens

To do or undertake something redundant, pointless, or futile. It refers to the city of Athens in the time of Ancient Greece, where silver coins were minted with the image of an owl (which were abundant in the city). Thus, to bring either owls or silver to Athens would be a useless venture. Creating a business to export olive oil to Italy is like sending owls to Athens! His plans to improve the economy by increasing taxes would simply be sending owls to Athens.