Travelling from Rotorua to Taupo is a popular journey for visitors to New Zealand. While one of the main tourist routes, you can find several less well known, hidden gems along the way to avoid the masses.
A little off the beaten track is the Waimangu Volcanic Valley geothermal area. Waimangu is home to the world's largest hot spring and a unique underwater geyser under a bright blue lake. Unlike the more commercial geothermal attractions, you can lose yourself for hours on the selection of walking trails (the Mt Haszard hiking trail is for the more adventurous). You can also take a boat cruise out on Lake Rotomahana to see features only accessible by boat.
The Waikite Valley hot pools are about a 25 minute drive south of Rotorua. These are quieter and less built up than some of the other pools in the area, and a favourite with locals as well as visitors from overseas. There is also a short walk to the spring that feeds the pool, providing an opportunity for some spectacular photos!
Rather than joining the crowds on the popular jet boat rides to Huka Falls, stop off on the way to Taupo and explore the Waikato river with NZ Riverjet. The Squeeze is an undiscovered gem, where you can squeeze through a tight rocky passage to get to a hidden hot waterfall.
A less well know attraction on the approach to Taupo is the Aratiatia Dam. The gates are released at set times, and the valley rapidly fills from a dry gully to a raging flowing river within minutes. Time your journey right and the release of the gates is announced by a siren before the water starts to flow. There are a variety of lookout points along the river, or it is easily seen from the road, just a 5 minute drive from the main State Highway 5.