A crane was used to secure boulders above the site to ensure the continued safety of workers involved in the development process.

JAC Group managing director Dean Cocker said everything was completed as planned.

"By December next year, there will be walkways, cliff climbing and freefall jumps, among other attractions," he said.

"There will also be a barge, restaurants, whiskey tours and cellar doors. This was preliminary work to ensure none of the workers were hurt by loose boulders or rocks."

Mr Cocker said the crane has since been removed from the site.

"We have carried out emergency works on the cliff and now that those works are finished the crane has been taken out."

The Penny Royal development is expected to finish by December 2015.