The Ultimate Guide to Cave Stream!

The Ultimate Guide to Cave Stream at Castle Hill, Arthurs Pass

Looking into the large funnel of white limestone with its black center, you might probably hesitate going any further. Caves have often been the focus of mystery and superstition among cultures around the world. But if there’s one cave that can make even the squirmish have a little bit of fun, its this one.

I had driven past ‘Cave Stream’ on highway 73 on the way from Christchurch to Arthurs Pass many times before. Always in a rush to get somewhere else, I never gave it the time. Today was the day however, I just had to check it out!


That’s about as simple as an explanation it can get. But it’s so much more than that. There’s something that invokes both excitement and dread when entering a cave. Our sense of adventure stirs and we are both drawn and repelled at the same time.

Read the sign before starting!

From the carpark, it’s a very short 5-10 minute walk to the south (right of the caving information sign) to the start. Going down the zig-zagging track, you head left at the river and follow it until the obvious cave entrance. You will be heading upstream in the cave.

Entering the opening, with the water flowing gently against you, it quickly turns a corner leaving daylight behind. Walking and wading through, the rock underfoot has a good amount of grip. The walls stay wide and the ceiling high.

The beauty of caves is in the simplicity.

Water has carved these places for millennia into smooth curves and winding passageways. There is no hurry in nature. Just steady progress, one water molecule at a time.


Read More:

How Much Does it Cost to Travel and Live in a Van in New Zealand?

My Swim With Wild Seals! The Kaikoura Seal Swim Experience


With brisk movement through the cold water, you soon make it to one of five small waterfalls you have to clamber up. While not difficult, they can be a challenge to anyone not familiar with some basic scrambling skills. However as a team and by helping one another, everyone can manage them. It’s the water level that makes the difference in how easy or hard the trip will be.

The cave twists here and there. Its just incredible!

Each little obstacle is similar to the last. In your hurry the exit will appear all too soon, or not soon enough depending on how cold you are!

The final 3 meter waterfall is climbed via fixed steel steps. The steps have grip on them to help. At the top, you crawl along the side while holding onto the chains. All this is done with some day light coming in, so is good for those not confident at climbing steps in the dark. Its the last challenge of the day.

Notice the chain to the right side and the steps in the rock in the center.

Back in the sun, you have another short walk back to the car, probably done in 5 minutes and is a good chance to warm up. Making sure to have spare clothes in your car is a good idea, a quick change and a bite to eat gets you back to room temperature in no time!

Cave stream is a fun little adventure that’s well worth putting on your New Zealand bucket list. No other cave has such good accessibility for everyone to enjoy.


While not technically difficult, there are some precautions you should take. These are:

► Wear as many warm clothes as you can.

Wool and Polypro (synthetics) are the best. A wetsuit is even better (but not required). Avoid cotton and definitely no jeans! Double up on socks or thermal bottoms if you can. A rain jacket or wool/polypro jumper can also be used and will help.

► Have a reliable light.

At least 1 spare light per person if possible, or one spare per group (not ideal). Head torches work best leaving the hands free. Do not use fire lighters or phone lights (but these could be backups). Spare batteries are recommended. And check all lights are charged before starting!

► Check weather.

Avoid before or after heavy rain or if the water is very cold. Rain will quickly flood the creek running through the cave, and is not the place you want to be when that happens!

► Check water levels.

The pictures below can give you some idea. Use your own discretion and check all signs at the beginning before starting. It should be no higher than waist level at the start, however due to people being different heights, the best way to check is to use visual reference guides like those below. This technique is used in the sport of canyoning and is more accurate than just saying 'waist deep' as this varies from short and tall people.

Notice between the 2 photos below how small the difference is? Don't be fooled, it looks small but makes a huge difference in the narrow waterfall sections!

This is a above average water level at the entrance of the cave. If it's over the red line on the photo, DON'T GO! Compare the photo to what you see and use the small holes in the limestone as reference points. Notice the right arrow and how the water is nearly touching the top of the long hole.

This is an ideal water level. Notice the right arrow and how much lower the water line sits to the long hole. Compare the photo to what you see and use the small holes in the limestone as reference points.

Discoloured water (it should be clear), debris floating or rocks rolling on the bottom are signs to wait for another day. There has been one death at Cave Stream due to high water levels, so please respect the water level. It will be narrow inside the cave channelling higher flows into dangerous hydraulics that can trap you. If it’s flooded, forget it!

► Never go alone

Although tempting, a single slip hitting your head will have severe consequences. You will be unconscious in the water with no one around. In summer, dozens of people go everyday. Go behind or in front of another group for extra safety if you choose to ignore this warning. Ask if it’s OK to join them. You will not have to wait long to find others to go with.

► Never leave someone alone in the cave.

A death has occurred in Cave Stream due to hypothermia. While hundreds do the cave every week in summer with no difficulties, if someone is having trouble in the cave due to the cold, never leave them alone. Apply first aid for hypothermia and send for help or get them out of there ASAP.


TIMES/LENGTH: 1 Hour average time to do the cave. Length of 600 meters. Walk in and out times are around 5-10 minutes each.

START LOCATION: Cave Stream Scenic Reserve car park, HERE.


◘ Headlamp/torch

◘ Helmet (if you have one).

◘ Warm hat/beanie

◘ Gloves if you have them

◘ Warm top

◘ Warm bottom

◘ Warm socks

◘ Shoes (trainers/sand shoes work best as they stay light when wet.)

◘ Wetsuit is optional, but if you have one, you will be very warm and can take your time.


Will boots be OK to wear?

Boots will be fine, however if you have sand shoes/trainers, these are better as they stay light when wet and will dry faster. The limestone rock has lots of grip, boots have no advantage over trainers. Do not go barefoot as the cold water will be incredibly painful on your feet!

How deep does the water get? How often are you in the water?

The deepest the water gets, provided you have followed the above guidelines for water levels, is waist deep. You are in the water all the time however, but the majority of the cave is ankle to thigh depth variations. You can often get out of the water for a bit on the sides. Some of the 1 meter waterfalls may end up wetting you a bit more from splashing. Unless you fall over (slipping ect), your top half should not get wet.

Is it cold?

Yes, it is cold year round, EVEN IN SUMMER!!! Spring melt water or winter conditions will make it even colder. Always keep moving and don’t linger in the cave unnecessarily. Carry chocolate for a extra quick boost of energy and WARMTH if you think you'll need it. You can keep these in a pocket, and trust me, chocolate really does make you warm! A beanie or warm hat can make a big difference as well. Also ensure you have dry clothes at the car for when you finish!

How much fitness/outdoor experience is needed?

If you are a hiker, spend any time outdoors regularly, or are in good, active shape with no bad health conditions, you will generally be fine. Unfit people should carefully assess the trip before going and seek advice. If you fall somewhere in the middle with your fitness, ensure you don’t go alone and stay with a group for support. You should always go in a group no matter your fitness of course.

Can I get lost?

Getting lost is hard. You simply follow the water upstream. Its a one way trip and you can always turn around and go downstream if you don't like something. There are many little short side holes/passages, none of which go anywhere. Just keep following the water upstream!

Is it worth taking a camera? Will it work in the dark?

Any waterproof camera is definitely worth taking! You can tether it to your wrist so you don't loose it. A couple of tips: As you never have to swim, try and keep water off the lens. A single water drop will ruin photos when using flash. If you are brave, you can take a good SLR camera and tripod and set up in several spots, and use 10-30 second shutter speeds with very still subjects to get good results. Use your torch to 'paint' the surrounding rock to highlight it a bit more. Ensure you use a dry bag for the camera in between shots as well! The odd water droplet falls from the ceiling in certain places.

I want to take a Gopro/action camera, will it capture the experience?

Newer Gopro models will do OK (5 & 6), but it will depend on how much light is around from your headlamps. Caves are dark! Have lots of light and try filming by hand and not mounting on head or chest. The footage of filming others as they walk by or clamber up things looks way better than your bobbing head. Trust me on this!

I want to take items that aren't waterproof! What do I do?

Unless you have dry bags, use a small back pack putting the items in at least 2 rubbish bags (strong ones), independently tied. Using 3 is even better. Try to avoid taking anything that can get damaged when wet. Travelling lighter is better and faster!

You can find the important information on the DOC website HERE, which also has a PDF download for it as well. Please check the DOC website and the weather before going!

And please, so we can enjoy this place for many years to come:


Cave stream surprised me and left me wondering why I waited so long to experience it. I can highly recommend it as being well worth visiting. Its a great introduction to caving environments, and you’ll feel like a grand adventurer exploring this place! Have fun and stay safe!


Please see the disclaimer HERE regarding all information provided on this post.

Do you like the content on the vertical adventurer? is it worth the price of a coffee?


This is a reader supported site, so every small contribution helps keep the website running and content (also coffee & cake) flowing. You can support me via a one time Paypal donation, or become a Patreon!


Not ready to buy me a coffee? You can still help me out by sharing this post on social media,  subscribing  to the blog, and following me on Facebook and Instagram!

Always remember this...

The environment is under threat from human impact! For your enjoyment and for future generations, please LEAVE NO TRACE! Respect natural places and leave them clean. You can learn more about the leave no trace principles HERE.