The red City Link bus serves the CBD every 7-10 minutes. The maximum fare is 50 cents. The bright green Inner Link bus serves the CBD and inner-city suburbs. The maximum fare is NZ$1.90. The bright orange Outer Link bus serves the universities, some inner-city and western suburbs, plus the Museum of Transport & Technology and the Zoo. Trains serve East, South and West Auckland from Britomart Station CBD. Ferries operate between the CBD and Birkenhead, Bayswater, Stanley Bay, Devonport and Half Moon Bay. HOP passes are available for train, bus and ferry services.