The biggest commercial port, Yokohama is 30km away via highway. Haneda international airport is 50km away, Narita international airport is 120km away and also provides easy access by car or train.
From Haneda international airport (HND)… by car 50min, by train 1h.
From Narita international airport (NRT)… by car 1h50min, by train 2h10min. (NRT is biggest airport in Japan. Almost international line arrive here.)
When use train… Nearest station is “Zushi”. It is 3Km from Hayama yacht harbor.
You can catch a taxi very easy at the station or car rental shop is 5min walk from station.