A specialist group of climbers and abseilers from the Fire and Rescue Service have been working to clear debris and old ropes.
The Gibraltar Museum has thanked the fire service for the potentially dangerous work.
Director Clive Finlayson said: “I am delighted with the support received from the fire service.
“It is highly satisfying to have different sectors of our community coming forward to make our World Heritage bid a success.”
Gorham’s Cave complex, located on the southeastern face of the Rock, was first inhabited some 55.000 years ago and contains Neanderthal engravings.
The museum is confident that Gorham’s Cave will be added to UNESCO’s list of world heritage sites when the committee makes a final decision next summer.