Waipu Caves are located in New Zealand's Northland around 2.5 hours north of Auckland. Free to access and with plenty of parking and a bathroom on site, there's no reason not to visit this spectacular spot of natural beauty. You can even camp at the caves for one night if you have a van or a tent. For free!
The caves are reached by walking around 200m across a paddock. You'll see a red and white sign directing you to the entrance and then you descend into the dark depths of the cave itself. There is no natural lighting (aside from the glowworms) once you're inside so do take a head-torch or regular torch with you. It's dark and slippy!
You'll need some form of footwear as the floor is dried mud which becomes super slippy when it's been raining or from the water of people who have recently climbed out of the creek. I was there mid-January and the creek was no deeper than mid-thigh height for me (I'm 158cm). I opted to wear flip-flops as they were all I had but plenty of people were wearing trainers or barefoot. I tried barefoot but the grip from the flip-flops was more useful.
Inside the caves are thousands of glowworms, a vast network of tunnels and some crazy rock formations. I highly recommend a visit, here are the highlights: