45 minute flight from Auckland to Napier, a quiet no-fuss airport. 30-45 minutes by car through the beautiful art-deco Napier (it was rebuilt after a quake during the period) and around the coastline to CK. You can do it as a day trip no worries.
Also home to one of NZ's great fuller bodied red wine regions. Hawkes Bay, and it's more specific microsite of Gimblett Gravels makes some awesome Cabernet, Merlot and Syrah.