A firefighting operation will continue into the night to quell a blaze which began on Sunday and has affected one square kilometre (250 acres) of the New Forest national park in Hampshire.
It began when a van caught fire on the A31 near Bratley Wood, forcing motorists to abandon more than 20 vehicles.
Lindsey Legg was with her husband and three children when they were forced to stop by police and leave their car. She said “women and children were walking with buggies” on the road and it had been “pretty scary”.
National Highways said the A31 dual carriageway through the New Forest would remain closed in both directions until further notice.
Hampshire and Isle of Wight Fire and Rescue Service said more than 120 firefighters had been working “in challenging conditions” to contain the blaze.
Forestry England said the blaze was under control, but it expected the firefighting operation to continue for several days.