Which is the longest book series?
Terry Pratchett's Discworld
The Lord of the Rings
The Lord of the Rings
Harry Potter
The Wheel of Time
The Chronicles of Narnia
Harry Potter
The Chronicles of Narnia
Harry Potter
The Wheel of Time
The Lord of the Rings
Harry Potter
The Chronicles of Narnia
A Song of Ice and Fire
Harry Potter
The Wheel of Time
The Chronicles of Narnia
The Lord of the Rings
Harry Potter
The Hobbit
The Fellowship of the Ring
A Song of Ice and Fire
The Chronicles of Narnia
Harry Potter
The Lord of the Rings trilogy
The Lord of the Rings Trilogy
The Hobbit
The Lord of the Rings series
The Wheel of Time
The Lord of the Rings
Harry Potter
The Chronicles of Narnia
The Hobbit
Lord of the Rings
A Song of Ice and Fire
The Lord of the Rings.
Harry Potter
The Fellowship of the Ring
The Wheel of Time
The Chronicles of Narnia
The Lord of the Rings Trilogy
The Lord of the Rings trilogy
The Hobbit
The Lord of the Rings series
The Lord of the Rings
Harry Potter
Lord of the Rings
Harry Potter series
The Chronicles of Amber
Fifty Shades of Grey
A Song of Ice and Fire
The Hobbit
The Chronicles of Narnia
The Wheel of Time series
Harry Potter
The Wheel of Time
The Lord of the Rings.
The Harry Potter series
Harry Potter series
The Lord of the Rings
The Chronicles of Amber
Lord of the Rings
The Hunger Games
The Lord of the Rings Trilogy
The Hobbit
The Fellowship of the Ring
The Lord of the Rings trilogy
Harry Potter
The Chronicles of Narnia
The Lord of the Rings series
The Adventures of Tintin
A Song of Ice and Fire
Harry Potter series
The Wheel of Time series
The Silmarillion
The Harry Potter series
The Wheel of Time
The Hunger Games
The Hobbit
Harry Potter
The Chronicles of Amber
The Chronicles of Narnia.
Harry Potter: The Fellowship of the Ring
Lord of the Rings
The Chronicles of Narnia series
The Outlander series
The Lord of the Rings
The Chronicles of Narnia
Harry Potter series
The Lord of the Rings.
Les Misérables
Harry Potter
The Hunger Games
A Song of Ice and Fire
The Hobbit
The Chronicles of Amber
The Silmarillion
The Harry Potter series
The Wheel of Time
Lonesome Dove
The Lord of the Rings trilogy
The Adventures of Tintin
The Lord of the Rings series
The Chronicles of Narnia.
The Chronicles of Narnia series
The Chronicles of Narnia
Harry Potter series
Lord of the Rings
The Wheel of Time series
The Hobbit.
Harry Potter
The Lord of the Rings
The Hunger Games
Forgotten Realms
The Hobbit
The Wheel of Time trilogy
The Chronicles of Amber
Mortal Engines Quartet
The Silmarillion
Harry Potter series
The Wheel of Time
The Chronicles of Narnia.
Harry Potter: The Fellowship of the Ring
The Chronicles of Thomas Covenant
The Chronicles of Narnia
Harry Potter
The Outlander series
The Lord of the Rings.
The Harry Potter series
The Hobbit.
Lord of the Rings
The Hunger Games
The Lord of the Rings trilogy
The Hobbit
The Outlander Trilogy
Lord of the Rings, Harry Potter
The Chronicles of Amber
The Wheel of Time series
The Lord of the Rings
Tomb Raider
Harry Potter series
Harry Potter
The Silmarillion
The Chronicles of Narnia
The Wheel of Time
The Hobbit.
The Hunger Games
The Hobbit
Tomb Raider Trilogy
The Harry Potter series
The Outlander Trilogy
Harry Potter
The Chronicles of Amber
Harry Potter: The Wheel of Time
Twilight Saga
Lord of the Rings, Harry Potter
Harry Potter series
Tolkien
The Outlander Series
The Chronicles of Narnia series
The Outlander series
The Lord of the Rings
The Wheel of Time series
The Hunger Games
The Hobbit.
The Hobbit
The Wheel of Time
The Chronicles of Thomas Covenant
The Chronicles of Narnia
Harry Potter
The Silmarillion
Mortal Engines Trilogy
Harry Potter series
Twilight Saga
The Chronicles of Amber
Harry Potter & Harry Potter
The Outlander Trilogy
Anita Blake
Forgotten Realms Trilogy
Lone Wolf and Cub
Tolkien
The Hunger Games
The Hobbit
The Harry Potter series
The Hobbit.
The Lord of the Rings series
Harry Potter
Lord of the Rings, Harry Potter
The Lord of the Rings
The Outlander series
The Chronicles of Thomas Covenant
The Wheel of Time series
The Outlander Series
The Chronicles of Narnia
Harry Potter series
The Wheel of Time
The Chronicles of Amber
Tolkien & Rowling
Lord of the Rings: Harry Potter
The Chronicles of Narnia.
The Hunger Games