Hundreds of people are set to tumble down the lawns of Parliament House in Canberra this weekend before visitors are formally turfed out of the grassy area.

Authorities have raised concerns that access to the lawns could increase the risk of a terrorist attack.

Restrictions are likely to be introduced over the summer period that would see the lawns fenced off.

Canberra man Lester Yao has organised a Facebook event to give visitors one last chance to roll down the hill, and 350 people have already indicated they planned to turn up on Saturday morning.

As a result, Mr Yao has spent the past few days trying to work out the logistics of rolling 350 people down the lawns at once.

"As you go up the lawn there's these lines of stones, and what I was going to do is if we get 300 people we do 100 per line and you stagger or stack them up on top of each other," he said.

But he said there were some issues he could not fix, such as the inevitable itchy skin that came from rolling down the slopes.

"The best thing is just getting some wet wipes and wipe yourself off afterwards," he said.

"I can't do anything about that one.

"Hopefully the fun involved in rolling down the hill will outweigh people's discomfort for half a day."

Being able to walk on hill is 'a beautiful symbol'

The move to beef up security has been controversial because Parliament House was originally designed to allow Australians to walk over the top of their political representatives.

It comes after protesters abseiled down the front of Parliament House, dyed the water feature red and super glued their hands to the public gallery during Question Time last month.

Sorry, this video has expired Protesters unfurl banner in front of Parliament House.

Mr Yao said as an architect he took a special interest in the proposed changes.

"Walking up the hill where the seat of Parliament is and being able to look and oversee the people who are the representatives is a beautiful symbol," he said.

"It sort of says that if you have a gate to the lawns you have to be judged before coming in to see if you are the right person, as opposed to having the individuals actually go there of their own free will and be part of this idea of democracy in Australia."

The lawns looked a little wet this morning after overnight rain, but Mr Yao said he was hoping that would clear by Saturday morning.

"Failing that, we could push forward with another great Aussie tradition, which is to get a couple of garbage bags and slide down," he said.