Uluru: The Mysterious Ayers Rock of Australia and the Secrets It Holds Underground

Emerging from the vast expanse of Australia’s Red Centre, the immense form of Uluru, or Ayers Rock, stands in stark contrast to the flat expanse that surrounds it. This ancient sandstone monolith located in the southern part of the Northern Territory, 335 km (208 mi) south-west of Alice Springs, has stood for hundreds of millions of years, drawing people to its base long before it became one of the world’s most recognized landmarks.

While its scientific formation can be traced to ancient geological processes, Uluru is more than a natural wonder shaped by time. The deeper significance of the rock lies in its cultural heritage, the stories woven around it, and the inexplicable experiences reported by those who visit. And the fact that much of its massive structure remains hidden beneath the ground only adds to its mystery.

Uluru is an ancient sandstone monolith formed over 550 million years ago, shaped by erosion and geological shifts. Once part of an extensive mountain range, it now stands as a single massive structure, with much of its bulk hidden underground.

The rock’s distinct red color comes from iron oxidation on its surface, while weathering has created its unique cracks, caves, and ridges. Despite appearing smooth from a distance, Uluru’s surface is deeply textured, shaped by natural forces over time.

For the Anangu people, the traditional custodians of the land, Uluru is much more than a striking natural feature. It is a sacred site, deeply embedded in their system of beliefs known as Tjukurpa. This term encompasses law, knowledge, and stories passed down through countless generations, connecting the landscape to ancestral beings who shaped it.

These stories explain the deep fissures, caves, and formations on the rock’s surface, each marking events from a time beyond memory. Some of these stories are shared with visitors, while others remain known only to initiated members of the Anangu, reinforcing the sense that Uluru holds knowledge not meant for all to understand.

Beyond its cultural importance, Uluru has long been associated with experiences that defy simple explanation. Travelers often speak of a sense of energy in the air, as if the rock itself exerts a presence. Some describe feelings of unease or overwhelming peace, while others report witnessing strange lights or hearing unexplained sounds. Though such accounts are anecdotal, they contribute to the idea that Uluru is unlike any other place.

One of the rock’s most striking features is how it transforms throughout the day. At sunrise, Uluru takes on a soft pink hue, while the midday sun reveals earthy reds and browns. As evening approaches, deep shades of orange and purple shift across its surface, making it appear as if the rock is alive with movement.

While science explains this as the interaction of light with the iron-rich sandstone, the effect is so dramatic that it can feel as though the landscape itself is breathing.

Uluru measures 2.2 miles (3.6 km) long by 1.5 miles (2.4 km) wide, with a circumference of 5.8 miles (9.4 km). But what many people don’t realize is that the visible part of the rock is only a fraction of its true size. Like an iceberg, much of its bulk is hidden beneath the surface. Estimates by scientists suggest that it extends at least 2.5 kilometers (1.5 miles) underground, possibly much deeper.

This means that what people see above ground is only a small portion of the entire formation, hinting at a geological past that stretches back hundreds of millions of years.

The underground portion of Uluru remains largely unexplored, but based on geological studies, it is composed of the same arkosic sandstone as the visible rock and is a remnant of an ancient seabed that hardened over 550 million years ago. Unlike limestone formations that often contain caves or tunnels, Uluru’s dense, compact structure suggests that there are no large hollow spaces or hidden chambers inside.

However, there is a network of underground water systems around Uluru, which has sustained life in the arid region for thousands of years. These water sources, known as subterranean aquifers, help feed nearby rock pools and support native plant and animal life. While there are many myths and speculations about secret chambers or extensive underground passageways, no scientific evidence confirms such theories.

The true mystery of Uluru’s underground portion lies in its immense size, which makes it one of the most significant hidden geological structures in the world. That said, the presence of underground water systems suggests that Uluru’s reach extends far beyond what is visible on the surface.

The surface holds many secrets too. Notably, a long-standing belief warns against taking rocks or sand from Uluru, a warning many visitors have ignored—only to regret it later. Hundreds of people have mailed pieces back, claiming to have suffered misfortune after removing something from the site. Whether these stories stem from guilt or coincidence, they have fueled a superstition that continues to grow.

Uluru is home to numerous caves and rock shelters, many of which contain ancient Aboriginal rock art that has been preserved for thousands of years. These paintings, created using natural ochres, depict ancestral stories, hunting scenes, and teachings passed down through generations.

The caves themselves served as important gathering places for the Anangu people, where knowledge, laws, and traditions were shared. Each site holds deep cultural significance, reflecting the spiritual connection between the land and its traditional custodians.

Climbing Uluru was once a popular activity, but it was permanently banned on October 26, 2019 out of respect for the Anangu people, who are responsible for protecting the site. Considered sacred, Uluru has long been a place of spiritual significance, with the climbing route believed to follow the path of ancestral beings. Since gaining official custodianship in 1985, the Anangu had requested the closure, urging visitors to honor their cultural traditions by refraining from climbing.

As the Anangu elders (the Traditional Owners) put it, “That is a really important sacred thing that you are climbing . . . You shouldn’t climb. It is not the real thing about this place. The real thing is listening to everything. Listening and understanding everything.”

Despite the climbing ban, Uluru draws people from around the world, not just for its striking presence but for the sense that there is something about it that cannot be fully understood. Whether it is the sacred stories embedded in its rock faces, the vast hidden portion stretching deep underground, or the unexplainable sensations felt by those who visit, Uluru remains a place where the unknown lingers just beneath (and above) the surface. In its silence, its shifting colors, and its immense presence, this sacred beauty never fails to invite reflection, respect, and awe. And yes, respect is certainly key for anyone who chooses to visit.

Found this interesting? Then do check out this other mysterious and stunning formation in Australia’s Northern Territory: The Devils Marbles.

Sources: 1, 2, 3, 4, 5, 6, 7