The hidden war relics that even locals don't know are on their doorstep

For the uninitiated, Cathcart is a small blip on the map, about 15km east of Bombala and about 80km south of Cooma. Due to its relative isolation, some call it deliverance country. Not me. I love it.

But this storekeeper isn't the only person to look sideways when I ask for directions to the World War II tank traps that are squirreled away in dense forest less then 10-15km south-east of town just below Big Jack Mountain Road.

And I can't blame them, when I first heard about the war-time relics, I thought someone was having a lend of me too.

Sure, I've explored remnant tank traps elsewhere along our east coast, including concrete tetrahedra traps on Newcastle's Stockton Beach that occasionally surface depending on swells and the sand blow.

And many years ago, while traipsing through scrub out the back of Tenterfield, I also stumbled across a purpose-built barrier of timber posts.

Some claim they formed part of the Brisbane Line, a defence proposal formulated during the war to "concede" the northern portion of the Australian continent in the event of an invasion by the Japanese.

But Cathcart is a long way from the Brisbane line.

However, this is no wild goose chase. These Cathcart traps aren't a myth. In fact, prior to this investigation, an obliging parks ranger from Bombala despatched a missive to my inbox containing a 2009 NSW national parks historic heritage inventory of the traps.

The inventory is far from detailed but does reveal the traps were built in the early 1940s by the 15th Battalion of the Volunteer Defence Corps, based in Bombala.

Further, the document reveals the tank traps were part of a broader "military complex" that included a wooden fort and two fox holes for explosives on a hair pin corner on Big Jack Mountain Road, which in the 1940s was still a major route between the coast and inland.

The purpose of the fox holes was like those on Poohs Corner on the Clyde Mountain where officers of the 14th Battalion of the Volunteer Defence Corps manned the corner between 1942 and 1944, guarding a tunnel that had been built beneath the road and packed with explosives.

The plan was that if Japanese forces landed on the south coast, the defence corps would detonate the explosives, thereby slowing any attempt by enemy forces to reach Canberra and beyond.

After the war, the entrance to the tunnel was filled with concrete and, of course, is now decorated with a proliferation of soft toys.

Back to the hunt for the Cathcart traps. After leaving the store, accompanied by fellow history hounds David and Lisa Hanzl and armed with a mud map handed to us by the ranger, we head deep into the wilds of the South East Forest National Park. Well, as wild as 10km from town can be.

Less than an hour later we spot our first timber post.

A rummage through the scrub reveals dozens of the waist-height posts, spaced out in four or five rows.

The timber obstacles, numbered in their dozens, run perpendicular to an abandoned road that is now a fire trail of sorts. The posts on the road itself were removed following the war to allow vehicular access.

"They really are textbook examples of timber posts traps," explains David referring to the 1941 Volunteer Defence Corp Manual (long declassified and available National Library of Australia), where in the Pamphlet No. 6 titled "TANK HUNTING and DESTRUCTION", under the section about "obstacles" and subsection "stumps", it instructs the following:

"Tree stumps will stop tanks when they are sturdy enough to raise the tracks off the ground by fouling the belly of the tank between the tracks. For this purpose, stumps should be not less than 12 inches [about 30cm] in diameter and should be 2 ft 3 ins [about 70cm] in height.

To prevent tanks manoeuvring between stumps the gaps must be reduced as in the case of trees. Belts of stumps must possess some depth; a single line will not stop tanks."

David explains, "They may not look like a serious defence, but they would have only been effective in stopping or slowing down the small, light tanks that the Japanese had at the start of the war."

Exploring the site requires caution, with several timber posts having succumbed to fire or rot or simply being removed, leaving the landscape pockmarked with partially hidden holes.

Having a leg trapped in one of these needs to be avoided at all costs, especially in this snake-infested back country.

The official inventory poignantly states "the military operations were kept 'hush-hush' in the local area, so civilians didn't know much of what was actually going on" adding "this is consistent with the general censorship policy undertaken by the Commonwealth government in regard to the war efforts on the home front".

But surely, over 80 years on, knowledge of these war relics should be better-known - they tell an important story from war time Australia. Oh, and despite 15-year-old preliminary advice from a heritage consultant suggesting the site be considered for a heritage listing, it hasn't. Yet.