A caravan fire spread between two cars outside a property in Whittle le Woods, near Chorley.
Crews from Bamber Bridge and Chorley were called to Shaw Brow just after 3.30am on Saturday, March 17.
A spokesperson for Lancashire Fire and Rescue Service said: "Officers found upon arrival that the fire involved two cars and a caravan.
"Four firefighters wore breathing apparatus and used two hose reels and one main jet to extinguish the fire.
"Crews were in attendance just over one hour."