Firefighters from across the county battled for more than three hours to put out flames engulfing five caravans in Redbourn last night.
Crews from Redbourn, Hemel Hempstead, St Albans and Harpenden raced to the Ver Meadows caravan site in the village to put out the fire, which began in one of the static homes at around 5.20pm but continued to spread to other smaller caravans. They were all completely burnt out.
Paramedics also attended the scene and police arrived to deal with crowd control.
In total five hosereels and three jets were used, along with four breathing apparatus kits. The blaze was controlled by 8pm but firefighters continued to make the area safe until 8.39pm.
Road closures were lifted at 9pm.
A crew from Hemel Hempstead also revisited the site this morning to check the area.
The cause of the fire is recorded as accidental.