Underground chambers

Underground chambers
Name	Underground chambers
Location	Hogwarts Castle, Highlands of Scotland
Book information
First appearance	Harry Potter and the Philosopher's Stone (only appearance)

The underground chambers are a series of rooms below Hogwarts Castle. There are six known chambers entered through a trapdoor in the third-floor corridor that were once used to protect the Philosopher's Stone. Each chamber has an obstacle to pass that delays a potential thief. The chambers are "miles under the school" where it is darker and colder.

History

In the summer of 1991, Albus Dumbledore thought that Voldemort was going to try and get the Philosopher's Stone. He was given the Stone for safe-keeping by Nicolas Flamel, and put it in Gringotts until he secured defences at Hogwarts Castle. He used the underground chambers that were found through a trapdoor in a section of the third-floor corridor.

He asked a few people on the staff to put an obstacle in each of the rooms. Rubeus Hagrid loaned Fluffy to put in the section of the corridor that had a trapdoor to the chambers. Dumbledore locked the door using a spell that could only be unlocked using the Unlocking Charm.

Voldemort and Professor Quirrell hatched a plan to take the Philosopher's Stone. They manipulated Hagrid into telling them how to get past Fluffy, and they enchanted a harp to put the dog to sleep. Harry Potter, Ronald Weasley and Hermione Granger worked out when he was going to try and get it, and tracked him through the corridor and in each chamber. The trapdoor was said to look the size of a postage stamp from the first chamber.

Chambers

First chamber

The first chamber has a Devil's Snare provided by Professor Sprout. The plant is designed to entrap and strangle the intruder. It has to be subdued with Bluebell Flames. Harry Potter, Hermione Granger and Ronald Weasley defeated the plant after Hermione had panicked, and Harry and Ron helped her find the solution of using the Bluebell Flames. They then went down a stone passageway to the next room.

Second chamber

The second chamber has a high, arching ceiling. It is well lighted. Professor Filius Flitwick provided hundreds of winged keys but only one of them will open the door to the next chamber. The room has broomsticks for those who want to get the key. The door is locked using an enchantment that even the Unlocking Charm will not undo. Harry, Ron and Hermione worked out it was the damaged key that had bright blue feathers because Professor Quirrell had used it and crumpled the key's wings up, and using a broomstick, Harry caught it.

Third chamber

The third chamber has a huge stone chessboard set up by Professor McGonagall. To get to the next room, a game of wizards' chess has to be won. The pieces are tall. Harry, Ron and Hermione took the black pieces of Bishop, knight and Rook. Ron led the game and eventually sacrificed the Knight to win, getting knocked out by the white Queen. Harry and Hermione then went to the next chamber.

Fourth chamber

The fourth chamber has a giant troll supplied by Professor Quirrell. He knocked the troll out when he passed through. It had not woken up by the time Harry and Hermione got to the room so they walked through to the next chamber.

Fifth chamber

The door that to enter the chamber is blocked with purple flames when someone has walked in. The door to leave through is blocked with black flames. The chamber has a table with nine potions on it and a logic riddle to solve supplied by Professor Snape. Drinking the right potion will enable someone to go through the next door or go back to the previous room. Two of the potions are simply nettle wine and three are poisons.

The smallest bottle enables one to go through the black flame. The round bottle will enable one to go back. Harry went forward while Hermione had to go back and tell Dumbledore he needed help. The riddle is:

Danger lies before you, while safety lies behind,
Two of us will help you, whichever you would find,
One among us seven will let you move ahead,
Another will transport the drinker back instead,
Two among our number hold only nettle wine,
Three of us are killers, waiting hidden in line.
Choose, unless you wish to stay here for evermore,
To help you in your choice, we give you these clues four:
First, however slyly the poison tries to hide
You will always find some on nettle wine’s left side;
Second, different are those who stand at either end,
But if you would move onwards, neither is your friend;
Third, as you see clearly, all are different size,
Neither dwarf nor giant holds death in their insides;
Fourth, the second left and the second on the right
Are twins once you taste them, though different at first sight.

Sixth chamber

The final chamber is provided by Albus Dumbledore. Dumbledore put the Philosopher's Stone in the Mirror of Erised. The only way to get the Philosopher's Stone out the Mirror is if it perceives the viewer does not want to use it for their own gain. It will put the mirror in their pocket.

Harry was confronted by Professor Quirrell and finally found out the truth: Quirrell was the one who wanted to kill him, he and Voldemort had joined forces and Voldemort was possessing him to the point that Voldemort's head stuck out the back of Quirrell's head. The mirror gave Harry the Stone and Quirrell attempted to kill Harry but even touching him hurt. Harry passed out, Dumbledore arrived to save Harry and Voldemort abandoned Quirrell, who was killed in the process.