To get there from Rotarua we had to drive through Middle Earth! You can stop and do some Hobbit Tours etc. but it's not our thing so that whole aspect of New Zealand is lost on us.
Instead, for our en-route adventure, we choose to visit Wairere Falls, a 45 minute walk each way, steep uphill to get there but really worth it.
It was a little disconcerting that the river had flooded onto the trail. "Flash flood" whispered in the back of my mind. If the rain had come on we'd have scarpered out of there straight away.
Unlike our next stop - Cathedral Cove. It's a 1.5 hr easy walk, but finding somewhere to park at the trail-head can be challenge due to sheer numbers of tourists. The trail to the cove feels like walking to a football match or concert - there's so many people. The upside was that we had good craic with the people around us. The trail was very muddy in places and those wearing flipflops provided entertainment for the rest of us! Everyone was in good humor and it was a fun encounter.
Cathedral Cove is beautiful, if crowded.
The caves and rock formations are massive and very impressive, so the tourist draw is pretty obvious.