The Budj Bim Cultural Landscape has long been regarded as a marvel of ancient engineering.

The sprawling water system in southeastern Australia was built more than 6,000 years ago — long before even the Egyptian pyramids took shape.

Ancient inhabitants of the region called Dhauwurd Wurrung, or Gunditjmara, devised the system of channels, weirs and dams as an extraordinarily complex trap for the eels that locals depended on for food. UNESCO recognizes Budj Bim as a World Heritage site today, but few suspected the aquatic system ran so far and so deep.

In fact, it took a catastrophe for Budj Bim, which lies in the heart of a 13,500-acre national park, to reveal itself in all its former glory. Bushfires, sparked by record temperatures and extended drought, have burned away the dense foliage covering the water system, allowing the full scale of Budj Bim to emerge from the flames.

"When we returned to the area, we found a channel hidden in the grass and other vegetation," Denis Rose of the nonprofit group Gunditj Mirring Traditional Owners Aboriginal Corporation, told CNN. "It was about 25 meters (82 feet) in length, which was a fairly substantial size."

"It was a surprise continually finding new ones that the fires revealed."

Built With Volcanic Rock

Lava channels and flows near Mount Eccles Lava channels and flows near Mount Eccles in Budj Bim National Park. (Photo: Robirensi/Shutterstock)

Just as the Egyptian pyramids were made with materials that were plentiful in the region, so too was Budj Bim built with the area's most ready resource: volcanic rock.

That building block came from rivers of lava that once flowed from a now-dormant Mount Eccles. According to the UNESCO website, the Gunditjmara used volcanic rock to redirect waters from Lake Condah — waters teeming with short-finned eel called kooyang.

A vintage image of the crater at Budj Bim. The long-dormant Mount Eccles is now a lake-filled crater surrounded by lava canals and caves. (Photo: Eugene von Guerard [Public domain]/Wikipedia)

"Authenticity is also evident in the practices associated with the trapping, storage and harvesting of kooyang; including the construction of stone weirs and weaving of fibre baskets," UNESCO notes.

What It Looks Like Today

While the Gunditjmara still call parts of the area home, their population, like that of many indigenous groups, has dwindled dramatically since Europeans arrived on the continent.

Over the millennia, their numbers reached an estimated peak of 7,000 but they number around 440 today.

But their achievements stand the test of time — even if it took a tragedy to reveal the full scope of them.

"I think what it really does is it's ... an important acknowledgement of the work that our Gunditjmara ancestors have done," Rose told the Australian Broadcasting Corporation on the occasion of Budj Bim becoming a World Heritage site last July.

"When I take people out to country I tell them this aquaculture system was first built 6,600 years ago — there's not many things on the planet that still exist today that are older than that."

Australian fires reveal ancient water system built long before the pyramids
After fires burned away the dense foliage, an ancient Australian landmark called Budj Bim is revealed in more depth.