Hawke's Bay Airport sits between Napier and Hastings, just a few minutes from the city centre. Air New Zealand flies direct from Auckland and Wellington multiple times daily. From the airport, you will need a taxi or rental car -- there is no public bus connection.
By road, Napier is about five hours from Auckland and four hours from Wellington. The drive from Taupo through the Napier-Taupo highway is particularly scenic, winding through pine forests and gorges before dropping down into Hawke's Bay. InterCity buses connect Napier with most North Island cities.