Scientists uncover world's oldest known pyramid inside a mountain

Scientists have uncovered an incredible secret about a seemingly 'natural' hill.

To the casual observer, the structure in West Java Province in Indonesia looks like a hill which has formed naturally.

It's covered in greenery, with four distinct sloping sides moving up the top which rounds off.

There's no denying that it does have a distinctive pyramid structure, but this structure in itself does form naturally.

For example, mountains in Antarctica appear to be pyramids, and have been carved out by winds and glaciers creating the distinctive straight edges.

Not so in the case of Gunung Padang.

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The surface of the structure features several stone constructions, so it has been clear for a long time that ancient people were there.

What was not previously understood was the extent of their involvement in the site, which went a good deal further than what you can see on the surface.

Authors of a new study wrote: “Radiocarbon dating of organic soils from the structures uncovered multiple construction stages dating back thousands of years BCE, with the initial phase dating to the Palaeolithic era.

“This study strongly suggests that Gunung Padang is not a natural hill but a pyramid-like construction.”

The study suggested that the structure began with the 'Unit 4', which is deep within it. It claims that this is a natural lava hill that was 'sculpted' into its current form over many years.

Like, many, many years. Thousands, in fact, as the most recent parts of the structure area thought to have been built around 2000 and 1100 BCE.

Scans from the study also revealed that there are 'hidden cavities or chambers' within the site.

Even more intriguingly, there is also evidence to suggest that it was buried deliberately a number of times over the years.

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The estimates for the earliest parts of the structure put it around 25,000 years ago. This challenges previous assertions that sophisticated building only arrived after agriculture around 11,000 years ago.

It also makes Gunung Padang older than the oldest pyramids in Egypt, from 2550 BCE, Mexico from around 900 BCE, and on Brazil's southern cost from around 5000 years ago.

But why were ancient people so keen on building pyramids?

The simplest explanation is that a pyramid is a very easy and stable way to build upwards. Weight distribution isn't something you have to worry about, because the wider base makes it an extremely stable structure.

Any people who wanted to build up started with pyramids because that was the easiest way to do it, until we figured out other ways to hold up big, tall buildings.