The Big Hole and Marble Arch Are Two Deua National Park Day Trip Delights

A bloody big hole, an ancient fern-lined slot canyon, and some gentle woodland walking combine to make The Big Hole and Marble Arch in Deua National Park a stellar day trip double-header, a few hours from Canberra and Sydney.

We Are Explorers acknowledges that this adventure is located on the traditional Country of the Yuin 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 Big Hole and Marble Arch trail is a 12km out and back Grade 4 bushwalk in Deua National Park. Lots of people turn around at The Big Hole but venturing on to Marble Arch is where the real magic starts. Tackle The Big Hole return in 1-2 hours or complete the full walk to Marble Arch in a leisurely 4-5 hours.

Read more: Remember to leave no trace

The Big Hole and Marble Arch Facts

Distance: 12km return (4km return to The Big Hole)
Duration: 4-5 hours (1-2 hours just for The Big Hole)
Elevation gain: 400m
Nearest town: Braidwood or Captains Flat

About The Big Hole and Marble Arch

At 100m deep and 50m wide The Big Hole sure lives up to its name. To get scientific, it’s technically a roofless limestone cave thought to be up to 400 million years old. It’s home to tree ferns, Welcome swallows, and lyrebirds who flit up and down the steep sides.

While The Big Hole is exactly what it says on the tin, Marble Arch is a slightly more misleading name. Nestled in a small glen, it’s more tunnel than archway. You’ll duck and weave your way over and under boulders as you follow the creek into the depths of the limestone arch, before emerging in a narrow slot canyon on the other side.

The Big Hole and Marble Arch History

Found on the traditional Country of the Yuin people, Europeans first stumbled across The Big Hole in the 1830s. Not long after, in 1862, a ballsy bloke called Boxall became the first person to descend into the hole, using nothing but four saplings, a rope, and a candle to abseil into the abyss. Since then, a few other people have explored the hole, including infamous swindler Alexander Fraser who defrauded Sydney investors of thousands of pounds in the late 1880s claiming The Big Hole was full of gold.

Nowadays, abseiling into the hole is heavily restricted but the lookout makes for a peaceful spot to enjoy some birdwatching and a picnic.

How to Get to The Big Hole and Marble Arch

The walk starts and finishes at Berlang Campground in Deua National Park. Berlang Campground’s just under two hours’ drive from Canberra, via Captains Flat or Braidwood. From Sydney, it’s closer to four hours, via Braidwood.

Once in Braidwood, plug Berlang Campground into Google Maps and you’ll be at the trailhead in half and hour. Head south from Braidwood along Cooma Road for 42km then turn left onto a well-signposted dirt road for Berlang/The Big Hole/Marble Arch. Berlang Campground is at the end of this 2WD-accessible dirt road.

A word of warning: Don’t put ‘The Big Hole’ into the GPS; Google will try and make you turn off early onto a private road.

Where to Stay Along The Big Hole and Marble Arch walk

We day-tripped from Canberra but would love to go back and stay at Berlang Campground. It’s a peaceful, grassy camping area just beside the Shoalhaven River complete with a few bush luxuries: plenty of fire pits and a long-drop.

It’s $12 per night for a site of up to six people (plus booking fee) with bookings required, but it’s usually pretty easy to snag a spot.

Skill Level

Beginner – Intermediate

The Big Hole is a great beginner friendly walk. The track is obvious and the walk uphill to The Big Hole is relatively gentle. The crux is really crossing the Shoalhaven River – I’ve been twice and both times the river’s been high enough to require a careful knee-high wade across the slippery riverbed.

The walk from The Big Hole to Marble Arch is a bit spicier. The track is still pretty obvious, but there are no distance markers and there are a few turns you need to pay attention for. The descent down to Marble Arch follows a steep spur, so make sure you’ve got gas left in the legs for the hike out.

Essential Gear for The Big Hole and Marble Arch

• Water
• Sun protection
• Grippy shoes for exploring Marble Arch
• Headtorch for exploring Marble Arch
• Swimmers for a splash in the river
• Binoculars

What it’s Like to Walk to The Big Hole and Marble Arch

First Stop – The Big Hole

Distance: 2km
Duration: ~1 hour

Fuelled by country bakery sauso rolls and the knowledge we’d survived another Canberra winter, we arrived at Berlang Campground excited to be out in the spring sunshine. In a testament to the walk’s relatively remote location, we were stoked to find we had the trail entirely to ourselves!

We set off from the campground along the narrow track to the Shoalhaven River just before 11am – a pretty leisurely start to our Saturday. After about 100m we came to the river and it was time to whip the trail runners off. The water was lower than our last trip but I was still in up to my knees at points and my feet were bloody cold by the time I got to the other side.

Once across the Shoalhaven, Pat set off to run the track and I meandered along enjoying the early spring birdsong. The trail rose steadily uphill from the river through dry open woodland until I reached the crest of a small hill. Then I was back into the treeline for a few hundred metres before reaching The Big Hole.

As with many geological marvels, the old cliché is true: photos just don’t do the hole justice. Looking out from the metal viewing platform I marvelled at the lush vegetation growing inside, struggling to compute that the tiny looking ferns were actually fully-grown trees.

If you like birding, be sure to look out for the Welcome swallows that surf the cool air currents in the hole and the elusive lyrebirds known to nest on the steep walls.

Read more: Bird Nerd Checklist: Are You One of Us?

Next Stop – Marble Arch

Distance: 4km from The Big Hole
Duration: ~1.5 hours

Just past The Big Hole the track descended to the valley floor via a series of steep switchbacks. It levelled off at the base, gently undulating for a few kilometres past large termite mounds and flowering spring wattles.

I met Pat about 2km from Marble Arch and we descended the steep spur down to the arch together. The track ended abruptly at Reedy Creek and if we didn’t know Marble Arch was tucked around a bend to the right, we would’ve easily missed it.

After taking a few minutes to enjoy the late afternoon light by the creek, we headed downstream, rock hopping our way along the creek to check out Marble Arch.

Tucked away behind a curtain of foliage, a series of tall tree ferns lead the way. The arch itself is fairly small, but it was fun shining the torch into tunnels running off the main cavern and squeezing under a low roof to emerge into the slot canyon on the other side.

After the cool temps of the arch, the return hike to the car felt like a bit of a slog, but we enjoyed a peaceful fish by the river to cap off a beaut day trip.

Tips For Hiking The Big Hole and Marble Arch

• Don’t forget your headtorch!

Marble Arch is more cave/slot canyon than light-filled archway so take a headtorch to explore it properly. I didn’t realise this so didn’t add one to my bag, but thankfully my lumen-hoarding boyfriend always comes prepared! In a pinch, your phone torch should also get you through.

• Navigate to Berlang Campground not The Big Hole

On a previous trip we put The Big Hole into Google maps and were told to turn off onto a private road a few kilometres before the actual turn. We nailed it this trip by requesting directions to Berlang Campground instead.

• Be careful crossing the river

The Shoalhaven River crossing isn’t the most dramatic but the water level can rise after rain and the river rocks are darn slippery. Use a hiking pole or large stick for balance if you’re not used to crossing rivers and be mindful of the current.

• Follow the path

Signage to Marble Arch is pretty minimal, limited to the occasional arrow scratched into an old metal plate. I personally love trails like this that make you feel like you’re in nature, rather than observing nature from a man-made footpath, but there were one or two places where I took a moment to pick up the trail.

The Big Hole and Marble Arch FAQs

How do I get to The Big Hole?

The Big Hole is located in Deua National Park in NSW between Canberra and the South Coast. To reach The Big Hole, drive to Berlang Campground in the national park, and follow the trailhead that crosses the Shoalhaven River early on. The drive is around 1.5 hours from Canberra and 3.5 hours from Sydney.

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