Head out of Bicaz on Route 12C towards Gheorgheni. At the aptly-named Gâtul Iadului (Hell's neck), the road enters Bicaz Gorge, a narrow 8km/5mi-long canyon linking Transylvania to Moldavia. The result of limestone rock erosion, the gorges boast spectacular scenery. Further along the Red lake was formed in 1837 after a landslide; its colour is due to ferrous oxide suspended in the water.