Containment lines have been working outside Eden on the southern side of Towamba Road, while fire fighters were also working hard to keep the blaze back from Nethercote and Towamba.

While heroic efforts have emerged from fire crews in areas like Wonboyn and Boydtown, the border fire has ravaged huge swathes of the south east to the Victorian border.

The fire broke containment lines near the border mid-afternoon on Saturday and raced northerly towards Eden at speeds of up to 6kmh fuelled by a strong southerly shift that brought with it clouds of smoke from the devastating Victorian fires which blackened the skies by about 4.45pm.

Residents endured a restless night with many evacuated mid-afternoon before those who remained were told to bunker down at Snug Cove Wharf or Aslings Beach.

Areas of Kiah and surrounding bushland were devastated with images of the town hall in ruin shared widely on social media, while two separate spot fires ravaged both northwest and south eastern corners of Ben Boyd National Park through the early hours of Sunday.

Around midnight the main fire front had been largely slowed south of Boydtown, while spot fires were kept at bay near Nullica River.

By Monday at least four homes were confirmed lost in Wonboyn by RFS volunteer Craig Butt.

"It wasn't pretty, very hot very windy and not a good place to be," he said. "We lost four homes and some out buildings, but no one got injured and we were very pleased with the outcome."

Fears remain for historic buildings including the Davidson Whaling station, the Seahorse Inn and Edrom Lodge, while photos from the lookout show Eden Chip Mill ablaze with plumes of smoke visible across the bay as rain helped to clear thick smoke on Monday.

Assessors are preparing to determine the number of homes lost, while Eden residents have not been allowed to return home.