Caves of Terror by Talbot Mundy, Fiction, Classics, Action & Adventure, Horror in Bloomington, MN

Athelstan King (hero of Mundy's early classic King -- of the Khyber Rifles) and burly and down-to-earth American Jeff Ramsden
follow the gray mahatma through a series of caves beneath an ancient temple, revealing different levels of wisdom and the limitations and tortures of those stranded at any one level. And at the end of their quest through this Dantean Inferno waits death . . .