The Knight's Den is the name of two secret sub-basement hideaways in Jolt City, each one used in turn as a base of operations for the first and second Green Knight.

Ray Cradle built the first Knight's Den beneath Cradle Manor; when the Manor was destroyed by Melvin Tightly shortly after Ray's demise, Anders Cradle had the house rebuilt but presumeably without the Knight's Den.

The second Knight's Den is located underneath the church of Martin Rock confidante Father Roy Riddle. Riddle discovered it shortly after moving into the parish, and theorizes that it may have been used by the 1940s era Pharos. Martin's current (as of early 2008) living conditions have greatly reduced the need for the Knight's Den-- and for Riddle.