But now, for the first time, the dirt has been dug up by archaeologists eager to find out more about our ancestors.
Perhaps the most interesting find has been the foundations of a house dating back to the 1300s.
The archaeologists said it is a hugely significant find, opening another door into the past and allowing us to learn more about how people used to live.
A flint scraper, used by people living more than 3,000 years ago, was also found. It would have been used to scrape animal skins, and as a sort of tool for eating food.
The dig was organised by the Belfast Hills Partnership and Queen's University Belfast. First-year archaeology students were given their first chance to explore an ancient site.
Some of those taking part said it had made them even more eager to follow this career path.
The dig has been going on for several weeks, but at the end of next week it will all be covered up again and restored to how it was before the archaeologists dug their trowels into the previously untouched land.
Lizzy Pinkerton from the Belfast Hills Partnership said they want to make sure it remains in good condition. They will now analyse all of the data and artefacts they have found.
It is unclear how many other potted sites like the one in Slievenacloy are waiting to be explored all over Northern Ireland, but the enthusiastic archaeologists say they are determined to find out.

The inquiry is being led by the complex case team of the Sexual Offences, Exploitation and Child Abuse Command.
Kids Company said it was not aware of the nature of any allegations and its priority was the safety of its clients.
Police want anyone with information or concerns to contact them or the NSPCC.
The police investigating team can be contacted on 0208 217 6538, while the NSPCC helpline number is 0808 800 5000.
Kids Company is run by Camila Batmanghelidjh.
The charity provides practical, emotional and educational support to some of the most deprived and vulnerable inner-city children.
In a statement Kids Company said its "first priority is the safety and security of all the children, young people and adults we support and protect".
It added: "The organisation operates robust policies and procedures that ensure all Kids Company's clients are protected and that staff work safely with clients at all times.
"Kids Company's policies and procedures are externally reviewed regularly by an expert consultant and are governed by a risk sub-committee comprised of senior clinicians and representatives from the board of trustees.
"All allegations of misconduct between Kids Company employees and clients are immediately reported to the police if required."
Earlier this month the charity faced questions about the way it was run and whether government funding would continue.
From the neolithic to the medieval period, a host of historical artefacts have been hiding in the Belfast hills.
[NEXT_CONCEPT]
An investigation into a number of allegations of crime involving the children's charity Kids Company has been launched by the Metropolitan Police, the BBC has learned.