After months of tireless firefighting, the Rural Fire Service has advised that, for the first time this season, all fires burning in New South Wales have been declared contained.

Efforts were assisted by drenching rains over the past few days, with Sydney enduring its wettest four days since 1990.

In the video above: Hellfire: The Battle of Cobargo (Part One)

The RFS says the rain helped firefighters extinguish more than 30 fires, some of which had been burning for months.

They include the Gospers Mountain megablaze northwest of Sydney, the large Green Wattle Creek fire southwest of Sydney and the Currowan blaze which ravaged the south.

‘Traumatic, exhausting’

“In what has been a very traumatic, exhausting and anxious bush fire season so far, for the first time this season all bush and grass fires in NSW are now contained,” the RFS said.

“It has taken a lot of work by firefighters, emergency services and communities to get to this point.”

Twenty-five people have been killed, more than 2400 homes have been destroyed and five million hectares burnt in the devastating blazes.

“The scale of these bushfires is unprecedented and NSW is experiencing the most devastating natural disaster in living memory,” Premier Gladys Berejiklian said.

“The bushfire season has left a huge scar on NSW.”

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NSW Emergency Services Minister David Elliott said the state has experienced one of the longest and most devastating bushfire seasons in history.

“The state is in mourning. The state is in grief ... for the heroes we never knew and who were there when we needed them most,” he told parliament on Tuesday.