Castle Rock is located at the opposite end of the island and is a detached rock formation jutting out of the water, which is connected to the island by a narrow walkway about fifteen-feet long. Castle Rock is described in chapter 6 as a "pink bastion" of stone close to a hundred feet high, with a sheer precipice emerging out of the ocean. On the top of the fort-like structure are numerous boulders that seem to totter on the edge of the cliff. When Ralph first climbs to the top of Castle Rock, he inches along the ledge of the square rock formation and slowly scales the massive structure. Castle Rock is simply a barren, unattractive environment with no natural life growing on it. While Ralph views the place as "rotten," Jack comments that it would make a great place for a fort. Shortly after Jack leaves Ralph's group, he establishes his tribe of savages and chooses Castle Rock as their headquarters. Towards the end of the novel, Roger hurls a boulder towards Piggy, killing him at the base of Castle Rock.  

In Lord of The Flies, Castle Rock becomes a more prominent and significant place as savagery descends on the island and the boys, who voted Ralph as leader when he first blew the conch and summonsed them using "the trumpet-thing,"(ch 1) become more influenced by Jack. Jack is the leader of "the hunters," so designated when Ralph is first voted in as chief and which gives Jack some measure of responsibility. Jack, however, is interested in hunting and consequences are never his concern. He acts irrationally and irresponsibly and his face paint seems to protect his identity, making his unacceptable actions less shocking in his mind. 

Castle Rock will become Jack's "headquarters" and is significantly different from the lush vegetation found elsewhere on the island. Whilst he and Ralph are searching for the "beast" they come across it and Jack recognizes it as a perfect place for "a fort."(ch 6) It is a "table rock," set marginally apart from the main part of the island. The steep slope and the "pink, tumbled boulders" excite Jack and with just a minimal trickle of fresh water, he is impressed, especially as the boys roll rocks down the steep sides- perfect for keeping the enemy out. Ralph has a different opinion of this "rotten place."