Canberra, Jul 20 (IANS): The first settlers of Australia reached the continent 65,000 years ago, about 15,000 years earlier than experts previously thought, a new archaeological study revealed on Thursday.

The archaeologists made the conclusion following an excavation at the Madjedbebe rock shelter near Kakadu National Park in northern Australia, one of the most important archaeological sites in the region known for its early rock paintings, reports Efe news.

The site was last excavated nearly 30 years ago by a group of archaeologists, who suggested that the site was between 50,000 and 60,000 years old, considered to be one of the first human settlements in Australia.

Between 2012 and 2015, archaeologists returned to the site to conduct new excavations.

The latest research included new techniques of analysis, like luminescence dating - which can determine when single grains of sand were last exposed to sunlight - allowing the research team to verify the age of the sediment surrounding the objects.

Researchers were also able to retrieve several tools in three different layers of sediment, including an ax, the oldest-known grindstone in Australia, and some early paints showing the oldest-known use of minerals.

"We found there was an incredible richness of evidence of wonderful human behaviour that we didn't really have indications of from earlier excavations," said Chris Clarkson, project leader from the University of Queensland.

Clarkson noted that the findings of his research, published on Thursday by the journal Nature, indicated a solid cultural continuity at the site across thousands of years.

The archaeologist added that this discovery could also contribute to a better understanding of humans' migration from Africa to Southeast Asia.