SUMMER PALCE BOAT TRANSPORT

Hi again - thanks for the info on the boat to the Summer Palace. I understand that it departs from the North Pier of The zoo ( near the Elephant Park ) - just wondering if I need to visit / buy an entry to the zoo in order to get the boat to the Summer Palace or can I just buy a ticket to the Palace from the Pier. Do you have any idea at what times the boat departs ?

Thanks - Jeff