vertiginous
adjective
extremely high or steep.
“vertiginous drops to the valleys below”
relating to or affected by vertigo.
I first came across the word “vertiginous” when walking the Levadas of Madeira
Madeira Levada Walks are trails along the paths beside the Levadas (mini-canals). The Levadas are situated on the steep sided slopes of the mountains and certainly induce vertigo when your eyes are drawn down into the valleys