These ferries ply the waters of Hauraki Gulf. They pick up passengers from the nearby islands and take them to Down Town Auckland. Some people commute from Devonport and leave their cars and bicycles near the ferry terminal.
When I was taking the photo, two ferries were there almost at the same time.
You can see at the back ground, the Sky Tower, which is the tallest tower in the Southern Hemisphere.
If you receive NZ Superannuation or you've reached the qualifying age of 65, you can use your SuperGold card to travel for FREE on Fullers' ferries from 9am weekdays, all day weekends and public holidays.