Fires have burnt more than 155,000 hectares inside a 300-kilometre perimeter, with many homes and other buildings feared lost.
The fire also claimed the lives of pilot Dick Lang, 78, and his 43-year-old son, Clayton Lang, who were killed when their car became trapped by flames near Parndana.
Most roads within the fire zone remain closed as work begins to replace key infrastructure.
On Monday, Reddit user kernpanic shared two photos of a winding road in the island’s Flinders Chase National Park.
One of the images, taken by Aaron Coleman in 2017, shows lush, green trees lining the long, paved road.
The second image, taken this week, bears a stark contrast, with what’s left of the burnt tree branches littering the ground.
One viewer said the images gave them a “severely broken heart”.
“How f****** devastating,” another commentor wrote.
“I'm so sad for my country and our beautiful wildlife.”
Another wrote the “contrast” between the two photos is “insane”.
“I can’t even comprehend everything that has happened yet,” they wrote.
Windy conditions have caused issues across the fire ground, with Country Fire Service crews dealing with a number of break-outs as they battle to fully contain the blaze.
The CFS says a large fire continues to burn at Cape Borda, towards the lighthouse, in inaccessible terrain.
On the north coast, there are a number of areas of concern around Snug Cove and Stokes Bay, where firefighters have responded to multiple flare-ups.
At Andamel, northwest of Vivonne Bay, there has also been renewed fire activity.
A controlled burn has been conducted in the Lathami Conservation Park, producing smoke in the area.
The defence force will deliver an emergency water purification system after a treatment plant was damaged by fire.
SA Power Networks crews are on the island assessing the damage to electricity lines and other equipment, with many kilometres thought to be brought down.
- With AAP
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