The Investigator Trail – Uncovering the Hidden Secrets of South Australia’s Eyre Peninsula

The Investigator Trail represents everything there is to love about the remote coastlines of South Australia – diverse, largely unchanged cerulean bays and towering sand dunes. Feel like the only person in the world on this 89km multi-day hike.

We Are Explorers acknowledges that this adventure is located on the traditional Country of the Barngala and Nauo people who have occupied and cared for the lands, waters, and their inhabitants for thousands of years. We pay our respects to them as the Traditional Custodians and recognise that sovereignty was never ceded.

Quick Overview

The Investigator Trail is an 89km figure-eight circuit hike that’s located in Lincoln National Park, South Australia. It can be roughly broken down into two loops, and is best done as a pair of overnighters, or in a 4-6 day traverse (which is my recommendation).

I’ve never shaken so much sand out of my shoe

Investigator Trail Facts

Distance: 89km
Duration: 3-6 days
Elevation gain: 1058m
Nearest town: Port Lincoln is just 15 minutes outside the national park

History of the Investigator Trail

I have a confession. One of my guiltiest pleasures, and maybe my most toxic trait, is how much I unabashedly love oil paintings of majestic old ships. So moody. So evocative. Stately even. It’s become evident to me through this love that I’m secretly a grizzled geriatric.

But given all this, you can imagine how interested I was in hiking a trail named after the HMS Investigator – the ‘leaky and rotting’ ship in which Matthew Flinders first circumnavigated Australia. Maybe it’s just the Texan landlubber in me, but I just find maritime history so captivating, I’m sorry.

And if I could give an award for coolest trail blaze of all time?!

The Investigator Trail more or less follows the footsteps of Flinders’ party as they searched the Eyre Peninsula for fresh water. This was one of the most perilous stops on their voyage, as they lost most of their crew to a shipwreck while they were dispersed in a ‘make-or-break’ search for water, and much of the region’s history and this expedition are detailed in signs throughout the walk.

The Barngala and Nauo people called the peninsula home before the arrival of Flinders and European settlers, and it was often due to the existence of their middens and wells that Europeans were able to find water on the peninsula at all.

This is reflected in the traditional name for Port Lincoln, Galinyala, which means ‘place of sweet water’, and becomes evident in Lincoln National Park as there wasn’t a single natural freshwater source for the entirety of the Investigator Trail, and all water is taken from rainwater tanks at campsites and shelters along the way.

You must also leave a peace offering for the bees

The open woodlands and coastal scrub have managed to survive on privations for millennia, and the wildlife on the mainland is sparse and mostly relegated to the skies and seas instead. A well-defined trail holds your hand through all of this, and never falls short of delivering some unreal waterfront campsites the whole way.

Pied oystercatchers (birds in the background) always pick the best real estate

How to Get to the Investigator Trail

A long-ass drive in a car is the only feasible way to reach this trail. It’s seven hours from Adelaide. But it’s possible to splash out extra cash on a flight to Port Lincoln and taxi to the national park if you like logistics, and you’ve got more money and less time.

The best place to start the Investigator Trail is from the Pillie Lake Trailhead because Pillie Lake is at the middle of the figure 8, and conveniently breaks the trail up into four sections. The second reason is because there isn’t really a great place to leave your car at the park entrance. Pillie Lake’s parking situation is a bit more concealed and convenient.

I hope you didn’t plan on swimming at Pillie Lake hehe

Where to Stay on the Investigator Trail

Myriad established campsites along the Investigator Trail have a range of amenities. Some sites cater more to car campers, and some which are hike-in only, are much more remote. There are even a couple of three-wall shelters where you can sleep or camp. The itinerary that’s laid out here stops at the most remote campsites and shelters, which are almost guaranteed to be empty most times of the year.

Even the wombat burrow at Brian Clarke Hut was empty

In a testament to how under-travelled the Investigator Trail is, the National Park Visitors Centre in Port Lincoln confirmed that hikers don’t need to book sites in advance. The safe option is of course to use the online booking form to check/book the sites you plan to stay at. But there’s decent reception at many points along the trail as well. So if you like flexibility, you could theoretically just rock up and camp if it’s free.

Read more: Hiking Gear: What’s Worth Carrying and What’s Not?

Skill Level

Intermediate

The Investigator Trail is a solid intermediate track. It’s well-maintained and easy to follow and has, like, one hill. That said, the trail can be rocky and the water carries still require some amount of bushwalking experience to tackle.

It helps knowing how much water you drink on a hike, how hot the Aussie sun can get, and how to have your gear dialed in since you’re camping in your tent every night. 25km+ days usually require a manageable pack and knowledge of your physical capabilities.

Read more: How To Survive Hiking in Hot Weather

Of course, if you’re taking your time on this trail, then there’s more room for flexibility.

Finally, they tell me it rains in South Australia in the winter, but we did this hike in January and I think my sunglasses and sun hoodie were the most crucial pieces of gear.

Read more: What To Wear When Hiking – A Beginner’s Guide

Sometimes the beaches are a little too windy for it to be very effective though

Essential Gear for the Investigator Trail

• PLB or InReach – Worth it if you’re hiking alone, especially since there isn’t reliable service along the entire trail
• Map or navigation device – I found the .gpx file to be extremely accurate
• Sun protection – That South Australian sun is BRUTAL. You’ll want a sun hoodie/wide brim hat, sunglasses, and water-resistant SPF 50+ because you’ll also want…
• Swimming (and snorkelling) gear – The beaches are naturally one of the highlights of this hike. It’d be crazy not to take full advantage of them, regardless of the season. A pair of goggles could be enough since there are extremely shallow reefs full of underwater life at these beaches.

Read more: Remember to leave no trace

I actually had to de-saturate this photo

What It’s Like to Hike the Investigator Trail

Perhaps it’s the lack of guaranteed water. Perhaps it’s the distance from cities that keeps most hikers away from this trail. Your reward for sallying out this far, as well as carrying a few extra liquid liters, will be immense. Revel in it.

The limestone that undercuts this coastline means that pristine beach after pristine beach rolls in like gentle breakers. Long, shallow bays make for unbelievable snorkelling stops.

We lunched on cliffs and beaches with Osprey and sea eagles. The Wanna Dunes felt like they could’ve been the Sahara Desert. We saw a dang goanna. An octopus stared at us. It was crazy.

The dunes and the beaches are naturally the highlight of this hike, and I could go on about them all day. But it’s worth mentioning that there’s also a fair amount of traipsing across dry, open woodlands and old powerline roads. It’s always easy underfoot, but some sections of the trail do feel a bit more like simple connectors between the highlights.

Although I’ll always have a place in my heart for mallee forests ❤️

With only handfuls of people in some of the busier car campsites, we camped alone every night and never saw another person on the entire 89km of trail. I don’t know if it’s because we were doing the trail in January, when the water is a bit less reliable, or what, but where WAS everyone?!

Day 1 – Pillie Lake to Woodcutters Beach Campsite

Distance: 8.5km
Duration: 3 hours

The hike begins at the information plaque at the car park, where you fill out the intentions book and snag a photo of the water tanks along the trail. This is a crucial piece of beta, because many of them aren’t listed anywhere online.

Or you can just use this one

It’s a short and easy first day, because odds are you’ll be coming from somewhere outside of the park and starting later on, but it gives you a good taste of what’s to come for the next couple days.

The trail begins by passing by Pillie Lake, a seasonal lake that’s bone dry and extremely barren in summer. The vegetation is sparse here and the silence is overwhelming. Things don’t leaf out too much until picking up an old powerline trail a few kilometres later. We peeped lots of Dusky woodswallows and heard lots of Rufous bristlebirds on this track and followed them until we hit the coastline.

The first beach and camp of the hike is Woodcutters Beach, which has great views back to the tuna farms of Port Lincoln and Boston Island. This was probably the warmest swim of the hike because of how protected the water is. We had to take advantage of it.

Read more: How to Stay Safe on the Beach

Day 2 – Woodcutters Beach to Carcase Rock

Distance: 25km
Duration: 8 hours

Beginning with your first real beach walk of many, Woodcutters Beach is a good indicator of how packed the sand will be for most of this trail.

Follow the plovers along the beach and cut up the dunes until you decide whether to continue hugging the coast or hoof it up to the top of Gaidyaba/Stamford Hill and see the monument that’s erected there to Matthew Flinders. Apparently it marks his vantage point across the peninsula, in their search for water. We were more than happy just drinking in the views.

Rounding Surfleet Point, you leave the views of Port Lincoln and get your first views of the much more remote Spalding Cove and Cape Donnington. Given our own timetable, we camped at Spalding Cove. Nothing beats falling asleep to the sound of waves.

Or waking up to a dang OCTOPUS at your campsite

Leaving Spalding Cove, you’ll encounter many of the busiest parts of the trail. It was very clear that these are the most popular sites in the park, as Fisherman Point, Engine Point, and September Beach all had multiple rainwater tanks, as well as more developed bathroom and car campsites.

The view from Donington Lighthouse is a highlight, as the seal and gull colonies on the nearby island were in full circus mode.

Make sure to grab enough water for the day/morning at September Beach. The eastern side of the cape is nothing but extremely desolate limestone cliffs that deserve to be immortalized in a painting. The waves pound against the shore, the gulls wheel overhead, the trail eventually opens onto the impossibly sheltered, blindingly blue waters of Yachties Beach and Carcase Rock.

This area of the park felt like it was probably the most under-visited and under-utilized, but maybe it’s just the constant sound of surging surf and wind that sort of lulls you into this sound-tunnel.

This whole section felt particularly meditative – but maybe it was just the unbeatable weather

Day 3 – Carcase Rock to Pillie Hut or Brian Clarke Hut

Distance: 26km or 30km
Duration: 8-9 hours

My recommendation is to hoof it all the way to Brian Clarke Hut, because it’s more spacious and open than Pillie Hut. The walking is relatively easy the whole way as well. Some of the highest cliffs in Australia are along this section, and the limestone formations whorl and swirl in the surf below.

After filling up water at MacLaren Point, your next major stop is Taylors Landing. It was nice of them to name a spot on this trail after me, but I must respectfully rebuff the epithet. I neither asked for nor wanted it. Anyways, you can launch a boat there if you want. It’s a beautiful beach too. Folks seem to love the point for fishing as well.

Taking in the incredible views

A long walk through inland mallee dumps you at Pillie Hut, which is little more than a small plaster shelter with a rainwater tank – more suited for a picnic or camping than an overnight sleep.

A bit further along a gentle climb is Brian Clarke Hut, which is a lovely three-walled shelter nestled into the imminent sand dunes. The water tank here was quite low in late January, but it hadn’t rained in almost two weeks either. The stars were immense.

Day 4 – Brian Clarke / Pillie Hut to Pillie Lake

Distance: 28 / 32km
Duration: 8-9 hours

Now for the wildest and most otherworldly part of the trail: the Sleaford-Wanna dune system. These wind-sculpted dunes are so dynamic and massive that they can’t really support much vegetation.

Apart from this, the mineralized air from salt and limestone has formed all these tiny little…wind stalactites? Miniature limestone/sand composite hoodoos? I don’t know. My undergraduate geology course is failing me. They were so insane though.

These babies take an hour to climb and about 30 seconds to descend

After doing a bit of sandboarding and glissading down the dunes, then giving the beach a little kiss, the trail follows the shores of the hyper-salinated Sleaford Mere. A ‘mere’ is another word for a large, shallow lake, which is apt as the shallow waters of the mere seem so inviting…but don’t be deceived.

The mud around the lake is easily waist-deep. Don’t ask me how I know. Also, we saw a goanna near some of the limestone overhangs along this section. The trail never fails to deliver surprises.

From Sleaford Mere, it’s just a few connector tracks past the park entrance and returning to your car at Pillie Lake. Time for a knockoff and some of the world’s freshest seafood just down the road in Port Lincoln. Or maybe one last swim in the beach. There are no wrong choices. Your investigation is complete!

Actually wait, what’s that?

Tips for Hiking the Investigator Trail

• Some of the campsites get pretty busy around holiday times. If you’re planning on going around then, call the visitors centre in Port Lincoln, or check the website bookings to see availability in your potential campsites
• If you’re fit, and start out early enough, this trail can be done in three days by hiking to Carcase Rock on the first day. There’s so much room for flexibility based on your timetable and fitness

This is the highest point on the whole trail

• Most websites recommend hiking in winter or the shoulder season, when temps are milder and water is more reliable. That’s a fair call. We did it in late January, and although there was water in every single rainwater tank, some of them were clearly beginning to get quite low. The tradeoff is that the swims were extremely refreshing every time. I think February and early March would be especially dicey. Plan accordingly, and it’s safest to always have a couple extra litres on you.
• On this note, temperatures were slightly more mild than usual for our hike. Mid 20s with full sun at midday was pretty brutal but manageable. Any more than that and I’d say you might start having some Type 2 fun.

FAQs for the Investigator Trail

Is the Investigator Trail suitable for beginners?

I probably wouldn’t make this my first overnight hike ever, unless I was with someone else more experienced. But there’s no reason why you couldn’t tackle it as long as you can read a map.

Can I walk the Investigator Trail anti-clockwise?

As there’s basically nobody else walking this trail, traffic is never an issue if you decided to walk it backwards. Thought I liked the build up to Wanna Dunes. I think it’s probably more important to plan route around your timetable.

Regardless of what direction you take, you’ll have some awesome scenery

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