The Highway 13 Fire that sparked north of Rifle last Wednesday is now at 80% containment.
According to officials, firefighters will continue to strengthen containment lines throughout Monday.
Due to the progress, a number of fire crews were relieved of duty on Sunday.
The wildfire is holding steady at just under 1,000 acres.
Investigators confirmed the fire was human-caused but were unable to determine exactly how it started.
The fire began adjacent to Highway 13.