the city is over 2,000 years old located deep beneath the earths crust. the only way down is hidden from the surface though some do manage to find it others are told how by a citizen. the trek down to the city is not all that safe due to being deep under the earth. once you get close to the city you will see it has a large dome around it with a single bridge leading up into it. the bridge would be over a large canyon to deep to see the bottom of. the city would be light by natural glowing bioluminescent crystals that have a dim glow to them all over the city to help keep your vision safe in the dark.