"tunnels both broad and narrow in the interior"

People,

The legendary Assro-Babylonian King Gilgamesh was
reported to have had a long conversation about the
underworld with the ghost of a dead companion. The
Greeks were constantly speculating about the depths of
the earth; one myth tells how the musician Orpheus
tried in vain to rescue his wife Eurydice from Hades.
the Poet Homer imagined an underworld waiting to be
explored, and the philosopher Plato wrote that there
were "tunnels both broad and narrow in the interior"
and in the center a god who sits "on the navel of the
Earth". Egyptians believed in an infernal underground
kingdom and there is a story that under the pyramid of
Giza there is a tunnel leading to the Earth's
Interior.

Dean