A group of tourists pose for a picture in front of the temple of the Parthenon atop the Acropolis in Athens, Greece, July 2, 2015. Prime Minister Alexis Tsipras called on Greeks to vote 'no' in Sunday's referendum on a bailout package offered by creditors, in a defiant address that dispelled speculation he was rowing back on the plan under mounting pressure. REUTERS/Jean-Paul Pelissier