The Varrock Library is located in a room on the north side of the Varrock Palace. It is run by Reldo, the librarian. There is only one searchable bookcase in the library, located near the north-west corner.
In The Knight's Sword quest, the player comes to the library in search of Reldo to learn about Imcando dwarves. The library also plays a role in starting the Shield of Arrav quest. Reldo refers the player to a book about the shield, which can be found on the bookcase.