On the line from La Oroya to Cerro de Pasco, high in the peruvian andes, there is only one double switchback. The Trains Unlimited charter train just arrived in Zigzag Arriba, shoved by G22CW 538 for about 1 km from Zigzag Abajo, and the switch is lined for the journey forward towards Cerro de Pasco. We are 12 km from La Oroya on about 3800 m a.s.l. The 132 kilometre long line is part of Ferrocarril Central Andino today.