Tarzan at the Earth's Core

The blending of jungle heroics with an underground world was such a unique twist. I wonder what inspired this crossover and how it shaped the story.

His resourcefulness and sense of justice stand out, but I’m curious if others felt he was different from his usual self in this particular story.

It added a whole new layer of danger and wonder, but I wonder if Burroughs always envisioned this setting or if it evolved during writing.