A woman has escaped with her life, trapped inside a building as a bushfire ripped through an historic rail museum in the NSW Hunter Valley.
Volunteers at the Richmond Vale Train Museum near Cessnock are counting their blessings after Wednesday's blaze reduced several irreplaceable exhibits to ashes but spared the life of their colleague.
"Our secretary was here on site, she was actually in the museum building as the fire came through. Basically it passed both sides of her but she is alright, she survived," museum chairman Peter Meddows told AAP on Thursday.
"She said she didn't think about it at the time, that it bothers her now more than it did then."
Caught in the path of the ferocious bushfire, the museum lost two kilometres of railway line as well as a number of restored historical trains and a coal hopper from 1880.
The final damage bill is expected to hit the $1 million mark.
The Richmond Vale bushfire that took off on Wednesday during an unseasonably hot day burnt more than 870 hectares, the Rural Fire Service said on Thursday.
"It's heartbreaking, you've got a program and you're working through it and you're achieving your goals, it's 38 years of work and we are slowly getting there and then you get this setback," Mr Meddows told AAP.
"We are all pretty dejected but we're determined to keep going."
Mr Meddows said the team was already working out how to recover from the loss.
"In a couple of weeks time we've got our family fun festival which is one of our major fundraising events so we've got to have something on for that," he said.