A lot of book series end after the third book. Some writers keep it even more simple by sticking with standalone. But occasionally, there are some book series out there that seem to go on forever, composed of dozens of books published through the decades.

The longevity of a series is a testament to its popularity. Though they sometimes drag on, their solid fanbase trusts the authors to keep delivering great stories again and again.

Long-running Book Series

In order to count as a long-running book series, the examples below must be published over the course of a decade. I’ve also disregarded word count, focusing on the number of books published instead.

Take note that this list focuses solely on novels. So even though some of these are part of expanded universes (stories that branch out into different media), we’re only focusing on the books themselves.

Many of these are also written by multiple authors during their long publishing history. To avoid confusion, I’ve chosen to only add the names of those who created the series itself.

From science fiction and fantasy to horror and mystery, below are a few of these longest-running series in literature.

The Guin Saga by Kaoru Kurimoto

First published: 1979

Number of books: 130+ (including 22 side novels)

Guin is an amnesiac warrior with a leopard mask magically grafted to his head. He remembers only three things: what he believes is his name, his fighting instincts, and the word “Aurra.” In search of his identity and purpose, he confronts a world brimming with demons, magic, and peril.

Kurimoto worked on the series until the 130th volume, after which she became too ill to write. According to the series website, her body of work remains the longest, single author’s body of work in the world.

After Kurimoto’s death in 2009, another writer (Yu Godai) took up the mantle as the series’ writer. The series has since sold more than 30 million copies and translated into several languages, including English.

2. Deathlands by Jack Adrian

First published: 1986

Number of books: 125

The cold war ends with an extensive exchange of nuclear weaponry between Russia and the United States. It devastates the planet, changing the geography, climate, and ecosystems for the worse. What is left of the United States soon becomes known as the Deathlands.

100 years later, civilization struggles to flourish. Crops grow weakly or not at all, hostile muties roam the landscape, and greedy barons hoard all military knowledge. A select band of survivors, led by Ryan Cawdor, explore the land in search of lost technology.

The written books end at the 125th volume due to the closure of Gold Eagle Publishing, the series’ exclusive publisher. It was picked up by another company, but the continuation only exists as graphic audio.

3. The Shadow by Maxwell Grant

First published: 1931

Number of books: 336 (including two anthologies)

Kent Allard is a famed aviator during World War I. After the war, he continues his fight against villains by becoming a vigilante. As The Shadow, Allan manipulates bad guys and police alike until the final confrontation, where he would take direct action.

The Shadow laid down the archetype of the superhero, including many tropes such as secret identities, sidekicks, supervillains, and costumes. Unlike modern superheroes though, Allard wasn’t averse to using guns and violence to solve crime.

The Shadow first started out as the mysterious host of the Detective Story Hour radio program. But listeners paid more attention to the sinister voice narrating the stories and soon requested copies of “that Shadow detective magazine” even though it didn’t exist. Writer Walter Gibson was soon commissioned to write novels under the house name, Maxwell Grant.

4. The Boxcar Children by Gertrude Chandler Warner

First published: 1924

Number of books: 160+ (including spin-offs)

Henry, Jessie, Violet, and Benny Alden are orphans. They flee from their grandfather, believing him to be cruel. After finding a boxcar abandoned in the forest, they decide to make it a home for themselves.

Eventually, they are found and returned to their grandfather, who turns out to be nice and wealthy. Throughout the series, the children go on many adventures around their neighborhood or the locations they visit with their grandfather.

Warner only wrote the first 19 books. But due to the series’ overwhelming popularity, publishers decided to continue releasing stories about the Alden children. The series is divided into mysteries and specials, with all of the specials written after Warner’s death.

5. Choose Your Own Adventure by Edward Packard

First published: 1979

Number of books: 184 (original series), 400+ (including spin-offs and crossovers)

Choose your own adventure is a series of gamebooks marketed toward 7 to 14-year-olds. You assume the role of the protagonist, which changes depending on the type of adventure. So in a fantasy adventure, one might choose between a fighter, an archer, or a magician. Roles are usually gender and race-neutral.

Every few pages, you’ll face a number of choices that dictate the flow of the adventure. The number of choices and endings, the ratio of good and bad endings, and your backward and forward progress through the novel are also randomized for a more unpredictable story.

Throughout its publication, the series has crossed over with many other series such as Indiana Jones, Star Wars, and Disney. And apart from the original series, other Choose Your Own Adventure series were created, with a few still being published to this day.

6. Fear Street by R.L. Stine

First published: 1989

Number of books: 163 (including spin-offs)

The Fear Street books take place in the fictional town of Shadyside, where supernatural anomalies, mysteries, and plain old murder abounds. These occurrences stem from a curse that has lived on through the ages, brought about by the Fear family and a mistake they made in the past.

Fear Street is meant for an older audience compared to Stine’s Goosebumps series. The characters are teenagers instead of preteens. And while Goosebumps features tame deaths, those in Fear Street are far more gruesome and graphic.

The protagonists change from novel to novel but since they’re all set in the same town, it’s not unusual for characters from one book to be mentioned in another.

7. Xanth by Piers Anthony

First published: 1977

Number of books: 45

In the world of Xanth, every human character is born with a magical talent. These abilities are unique to each person, with no ability repeated throughout Xanth’s long history (though near-identical ones do appear). What a person gets can be anything from changing colors to turning back time.

The protagonists of each book vary. Sometimes it’s a man, a woman, a child, or a non-human. This gives the series a well-rounded perspective of its world. It’s also famous for its many puns, which are all fan-submitted (at least, in the early books).

Anthony originally intended the series to be a trilogy, but devoted fans soon convinced him to continue writing the story. It is now an open-ended series.

8. The Destroyer by Warren Murphy and Richard Sapir

First published: 1971

Number of books: 153

Remo Williams is a cop who is framed for a crime and sentenced to death. The government fakes his death to train him as an assassin for CURE, a secret organization that works outside of the law. There, he is taught a wide variety of fighting techniques that range from secret martial arts to modern weaponry.

Though the series starts in an “ordinary” world, elements of science fiction and fantasy are later inserted into the narrative. From cyborgs to vampires, Williams has fought almost all kinds of foes imaginable.

Over the decades, the series has switched publishers multiple times, taken up ghostwriters, and has been adapted into different media.

9. Fantomas by  Marcel Allain and Pierre Souvestre

First published: 1911

Number of books: 43

Fantômas is the ultimate criminal—intelligent, ruthless, and extremely elusive. For every crime that goes unsolved, it’s a safe bet that he’s the one behind them. As a master of disguise, no one knows his real identity, and is able to get away with his crimes by impersonating anyone.

The title character is one of the most famous in crime fiction, especially due to his willingness to go further than any other villain. His crimes are (supposedly) due to his disdain for modern civilization. He is merciless, sadistic, and loyal to no one.

Souvestre co-wrote 32 books out of the series, until his untimely death. After that, Allain continued the series for 11 more novels. It has since inspired many films, tv series, and comic book adaptations.

10. Uncle John’s Bathroom Reader by the Bathroom Readers’ Institute

First published: 1988

Number of books: 35 (main series), 100+ (including spin-offs)

Uncle John’s Bathroom Reader is a series of books that contain trivia and short essays on various subjects. As its name implies, it’s meant to be read while in the bathroom. Much of its content is intentionally humorous.

Some recurring features are origins of words and phrases, urban legends, funny court transcripts, strange lawsuits, and reader-submitted content. Throughout the books, there are short, random facts written as footnotes on each page.

The main series has been consistently published every year since 1988. Volumes dedicated to a single topic (such as celebrities, animals, places) are also frequently published.

11. 1632 by Eric Flint

First published: 2000

Number of books: 27 (90+ including anthologies and The Grantville Gazettes)

1632 is an alternate history series in which the fictional town of  Grantville, West Virginia suddenly finds itself transported back in time to 17th century Europe.

A wide cast of characters must then adapt to a less advanced lifestyle while dealing with the Thirty Years’ War. Modern ideologies, practices, and knowledge clash with the authoritarian and religious-centered societies of the past.

The first book was only meant to be an experimental, stand-alone novel. But after receiving much attention, Flint decided on turning it into a series that is collaboratively written by Flint and other authors. Many of its canon are also drawn from The Grantville Gazettes, a bi-monthly magazine of fan-written works.

12. The Baby-Sitters Club by Ann M. Martin

First published: 1986

Number of books: 131 (original series) 200+ (including spin-offs)

Kristy, Mary, Claudia, and Stacey all love taking care of kids. It gives them a chance to have fun while earning money. And since they’re all already babysitting anyway, Kristy decides on forming the Baby-Sitters Club.

What they didn’t expect is the amount of trouble they’ll encounter. From prank calls and cranky kids to wild pets and dishonest parents, running a club’s not as smooth as they thought it would be.

This series was initially planned as a four-book series. Due to popular demand, it was kept running until publishing ceased in 2000. Martin is estimated to have written from 60-80 books in the series.

Reading Lengthy Stories

We’ve all fallen in love with a book and decided to follow it to the very end—however long it takes. It’s that kind of attention that keeps a series going.

Some of these series start out great, but often times they’ll turn into nightmarish reads. This is either from the sheer amount of information that needs to be digested or from a declining level of quality in writing. Long-time fans aren’t easily dissuaded though.

Either way, it’s definitely a big commitment to take on a lengthy book series. It might take you years of reading, during which you might decide to drop it, or (in my case) push on to the next novel, wondering what else the story has to offer.

Also, consider that many of these series are written by more than one author. Depending on their skill to create one narrative voice, some books might be a miss for you.

What’s the longest book series you have ever read? Share them in the comments below!

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