Waipū Caves is limestone country inland from Waipū, about 40 minutes' drive north of Mangawhai. There are two ways to see glow-worms there: the free, unguided cave beside the council reserve at the end of Waipū Caves Road, or a guided tour of the Milky Way Glowworm Cave at the privately run Waipū Caves Farm Park on the same road. There's also a 2 km DOC track up through the scenic reserve.

How do you get to Waipū Caves from Mangawhai?

Head for Waipū, either up the coast road through Langs Beach and Waipū Cove or inland to State Highway 1. DOC's directions: from SH1, take Shoemaker Road from Waipū, or Springfield Road from the north, to reach Waipū Caves Road. The farm park is at 567 Waipū Caves Road. The public reserve and cave entrance are along the same road. The last stretch is rural road, so take it easy.

The free cave or the guided tour?

The free cave (by the council reserve). No booking and no fee. You walk in on your own, with your own torch, over wet rock and through water. DOC says the caves are wet and slippery inside and the inner cave is for experienced cavers only. Most people go just far enough to see the glow-worms, turn their torches off and wait for their eyes to adjust.
Milky Way Glowworm Cave tour (Waipū Caves Farm Park). Guided, on an easy-access path, with photos allowed. The shorter Milky Way tour takes 60 minutes and suits all ages: $45 for adults (16+), $30 for kids 5–15, free under 5. The longer Starburst tour takes 90 minutes and goes deeper, to the Starburst Cathedral: $80 adults, $50 for ages 13–15, and no children under 13.

With young children, wanting to stay dry, or when there's been rain, the tour is the easier choice. If you've got good shoes and a strong torch and the weather's settled, the free cave is a proper little adventure. The farm park runs tours daily (more in summer), is closed on Christmas Day, and keeps some room on each tour for walk-ins, though it recommends booking online.

Is the Waipū Caves walk worth doing?

The DOC track starts at the Whangārei District Council reserve by the cave entrance: find the orange post and cross the big concrete culvert. It's 2 km and climbs steeply through the Waipū Caves Scenic Reserve, past limestone outcrops, grass and regenerating bush, to a gate onto private farmland on the ridge. From the top, DOC says, you look out over Whangārei Harbour, Bream Head and the Hen and Chicken Islands. Come back the same way. Note that the track doesn't go to the caves. The cave entrance is across the reserve, before the track starts.

What to wear and bring

A proper torch for the free cave, one each, plus a spare. Phone torches run flat and you need both hands.
Shoes that can get wet and muddy, with grip. The cave floor is wet and the track can be muddy and slippery.
A change of clothes and a towel in the car. The free cave usually means wet feet at least.
Water and a picnic. DOC notes a large flat grassed area for picnics and a public toilet run by the council at the reserve.

Safety

Caves can flash flood. DOC's advice is to check the forecast first. Don't go into the free cave in or after heavy rain.
Sinkholes are common in karst country. Stay on the track and keep small children close.
The inner cave is for experienced cavers only. If you aren't one, turn back where the walking gets hard.
Turn your torch off to see the glow-worms, and don't touch them or shine lights at them for long.

Pair it with

Waipū township is on the way back, with the Waipu Scottish Migration Museum and visitor information and McLeod's Pizza Barn. Then come home via the coast for a swim at Waipū Cove or Langs Beach. On a wet day, the guided cave tour is one of the better rainy-day options within reach of Mangawhai. The farm park also runs the Cave Concerts in the largest chamber.