The ring of fire is about 50 feet thick. Characters take 3-18 points of damage per round. Any flammable items have an 80% chance of catching fire per round unless wet. Water will take 1 round to dissolve. A wall of ice will melt in 1/2 turn, leaving a path for 1 round.
If the person is drenched he will only take 1/2 damage. A cold spell will cancel out the heat for half its normal radius.
Inside the ring, in the middle, which can barely be seen from outside, are five scantily-clad females, charisma 18, 15, 17, 18, and 17, chained to the rocks. When the characters reach 10 feet from the females, they will disappear*.
The ring fire will double its thickness, and close in at five feet per round, taking 10 rounds to completely close. One of the five rocks†, when moved, discloses a hole. The hole is completely dark and cannot be lit. It is a one-way portal to the middle of the city.
For the circles, see map CD.