C285 Extinction on Extreme Night(part Ii)

Arthur was led by Guinevere to the depths of the ground.

This was a huge hole in the ground. The underground igneous strata of London were naturally formed by the movement of the earth's crust, and were a thousand square feet deep. The deeper they went into the earth, the colder and drier the burrow that was made from the granite was. This place was indeed very suitable for preserving treasures