Step Assembly and Vehicle

A step assembly for a vehicle has first and second arms pivotably attached to brackets which are mountable on the chassis or body of a vehicle. The arms pivot about coaxial axes defined by the brackets. A tread is mounted on the arms. The tread is pivotable between an open position and a closed position. Respective biasing elements act between each arm and bracket to bias the tread into the closed position. When the step assembly is mounted on the vehicle adjacent to a compartment defined by the vehicle body the tread acts as a door when in the closed position and a step when in the open position.