KiwiRail Holdings Limited is a New Zealand State-owned enterprise responsible for rail operations, which trades as KiwiRail. Headquartered in Wellington, New Zealand, KiwiRail is the largest rail transport operator in New Zealand. Since July 2010 John Spencer has been the chairman. KiwiRail Scenic Journeys, Tranz Metro, Interisland Line and KiwiRail Freight are all subsidiaries of KiwiRail.