The Royal National Park was closed and hundreds of people escorted to safety on Saturday, as firefighters battled two out-of control bushfires near Wattamolla in Sydney's south.

Two hundred people were evacuated from Wattamolla Road to Bundeena by NSW Rural Fire Service and NSW Police in the afternoon, while other visitors were advised to "head to the beaches".

An out-of-control bushfire burning in the Royal National Park, as seen from Bundeena. Credit:Brook Mitchell

"They're providing the best protection given the fact a lot of the escape routes are through the middle of the bushland which isn't safe at the moment given the intensity of the fire," a spokesman for NSW RFS said on Saturday.

Private boat owners alongside NSW Surf Life Saving, NSW Police and Marine Rescue NSW vessels at Garie Beach had evacuated up to 80 people by the evening.