Thousands of scouts from around Australia and across the world have descended on Appin, south of Sydney, for the 2016 Australian jamboree.

Youth leader Ben Cherry-Smith said it was an important event for every scout.

"It's a life-changing experience," he said.

"For most scouts this will be their one and only jamboree."

More than 300 international scouts are visiting this year, from as far away as the United Kingdom.

Scouts from Timor Leste and Papua New Guinea have also been given financial support to attend.

Papua New Guinean scout leader Lohia Kauna said he was slightly overwhelmed by the scale of the event.

"I'm excited. It's really new to me," he said.

Scouts from East Timor at the jamboree. ( ABC News: Nick Dole )

Not just about badge collecting and tying knots

The tent city is better resourced than some country towns, complete with a heliport, skate park, water slide, radio station and entertainment arena.

It is big enough to quality as Australia's 35th largest town, according to the scouts.

Its medical centre can care for up to 200 patients and includes a pharmacy, X-ray machine and physiotherapy services.

Director of health services Allan Kirkpatrick said the centre takes the pressure off the public hospital system.

"Minor injuries and illnesses, we'll manage ourselves," he said.

"It's a new city and most cities have a medical centre and we're it."

Over 10 days, scouts will take part in dozens of activities including adventure races, a giant swing, joy flights and water slides.

Circus training is also being offered, including acrobatics.

Circus leader Ayla Jones said scouts is about more than just badge collecting and tying knots.

"That's still part of it and it's still important, but we want to make sure we're moving into the 21st century," she said.