Wondering About The Longest Book Series? Here Are 11 That Might Surprise You

A book series is the literary equivalent of a long-running television show.

They feature in-depth plots and detailed character development, making them more engaging to many readers.

Today, we’re looking at some of the longest-running book series of all time.

We tried to add something for everyone and hope you find an option to test drive.

What Is a Book Series? 

Stand-alone novels consist of one book. Conversely, book series have multiple volumes.

Some compilations tell a single story; others branch off and tell distinct tales set in the same universe. 

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Though exceptions always exist, common characteristics of book series include:

  • Usually three or more books
  • Character consistency across multiple volumes
  • Ongoing storylines and character development that span numerous books
  • A heightened reader engagement factor due to prolonged exposure to characters and worlds

Frequently, novels in book series end with cliffhangers to keep readers glued. Besides, what better way to get people to purchase the next installment!?  

Typically, stories in a series written by one author are marked by a consistent tone. The same may hold for ones penned by multiple writers, but that’s not always the case. So, if you value style consistency, look for a series with only one author.

11 of the Longest Books Series that Might Surprise You 

It’s difficult to definitively name the longest book series in the world because differing criteria muddies the waters. That said, we’ve done our best to pick out contenders.

Some of them are done and dusted, and new volumes won’t be added because the author passed away, the publishing house closed, or the story has reached its conclusion. Others, however, are still going strong.

We’ve made an effort to pick options from a breadth of genres while also being mindful of answering the ultimate question: What is the longest book series of all time?

The Shadow

Maxwell Grant published the first Shadow book in 1931. The main character is a legendary WWI pilot, Kent Allard, who continues fighting for justice after the war as a vigilante known as the Shadow.  

Many literary scholars credit Grant for creating the first modern-day superhero. He uses costumes to create alternate identities, is challenged by recurring villains, and has a coterie of sidekicks that help him nab the bad guys. However, unlike most of today’s Marvel and DC superheroes, the Shadow is pro-weapon and regularly uses guns and ultra-violence to serve justice. 

Notably, The Shadow started as a radio personality on the Detective Story Hour. The program was such a smash hit that people started asking for related books. Ultimately, Walter Gibson was commissioned to fulfill the public’s wishes and write stories under the pen name Maxwell Grant. 

First Published: 1931

Number of Books So Far: 336


Penned by American writer Piers Anthony, Xanth is one of the most popular and longest fantasy series ever published.

Every human in the Xanth world has a magical ability known as a “talent.” Though each one is different, some are very similar. Talents vary in intensity. For example, one person can reverse time, and another can make a leaf wither just by looking at it.

Like many fantasy books, the Xanth world features several species, including elves, centaurs, fauns, dragons, goblins, ogres, zombies, and curse fiends.

Non-humans also exist in the magical world, and each book focuses on a different protagonist.

The Xanth book series is known for its puns, many of which readers submit.

First Published: 1977

Number of Books So Far: 45

Nancy Drew Mystery Stories

Journalist Mildred Augustine Wirt Benson wrote the first Nancy Drew mystery story, The Secret of the Old Clock, under the pen name Carolyn Keene. She wrote many of the early volumes, but in the 1950s, more authors joined the fold; however, many continued to use the pseudonym.

Nancy Drew is a girl detective in the mold of the Hardy Boys. She lives in the fictional town of River Heights with her attorney father and beloved housekeeper. In earlier books, she was described as a 16-year-old; in later editions, she’s 18. 

Extremely intelligent, capable, and inquisitive, author Bobbie Ann Mason once described the iconic character as “immaculate and self-possessed as a Miss America on tour. She is as cool as a Rock Star and as sweet as Betty Crocker.” 

Nancy is often helped by her two cousins, Bess Marvin, and George Fayne. She also has a boyfriend, Ned Nickerson, a college student who occasionally lends a hand.

Though the original Nancy Drew Mystery series is over, the franchise has spawned several other compilations, including the Nancy Drew Diaries, which are still being published today.

First Published: 1930

Number of Books So Far: 175

The Destroyer

Remo Williams is a former cop who was once framed for murder. Although he was sentenced to death, the U.S. government faked his demise as they recognized his skills and believed he would be an excellent addition to CURE, a secret agency of assassins established by John F. Kennedy.  

Chiun is Remo’s martial arts sensei and father figure. Together, they work outside the law to solve crimes and bring dangerous criminals to heel. 

Originally, The Destroyer series was set in the “real world,” but supernatural elements were added over the years.

Initially, Warren Murphy and Richard Sapir wrote the books. But as it grew, ghostwriters took over.

First Published: 1971

Number of Books So Far: 153

Sweet Valley High

Twins Jessica and Elizabeth Wakefield are two all-American girls living in the fictional Sweet Valley, California, alongside their parents, Ned and Alice. A little bit of a soap opera, fantasy-adventure, and romance all rolled into one, the books are most often classified as young-adult fiction.

First published in the early 1980s and written under Francine Pascal, a universal pen name for a conglomerate of ghostwriters, the Sweet Valley High books were an immediate success that spawned several spin-offs, including Sweet Valley Confidential and The Sweet Life, which followed the characters into adulthood.

First Published: 1983

Number of Books So Far: 181

The Horus Heresy

Warhammer 40,000 is the world’s most popular miniature figurine wargame, and it serves as the setting of The Horus Heresy. Specifically, the books center around an ongoing civil war lasting over 10,000 in the dystopian Horus Heresy galaxy. 

Initially, it was meant to be a trilogy, but its popularity spawned more books. 

Like most long series, The Horus Heresy features many characters, but the main ones include Lion El’Johnson, Leman Russ, Magnus the Red, and Ferrus Manus. 

The books are written and illustrated by a team of writers and artists and published by the Black Library, the literary division of Games Workshop.

First Published: 2006

Number of Books So Far: 62

Perry Rhodan

Many people cite the Perry Rhodan, der Erbe des Universums (Perry Rhodan, Heir to the Universe) series — commonly called Perry Rhodan — as the longest book series currently in existence. Others argue it’s the longest of all time due to word count. 

Remarkably, the German space opera has sold two billion copies internationally. Though the first edition was published in 1961, the first English translation didn’t hit shelves until 2021.

K. H. Scheer and Walter Ernsting originally developed the concept and only planned on publishing 30 to 50 novellas. But the people demanded more, so the series is still going strong, weighing in at over 5,000 volumes. Today, a large group of writers and artists work on it. 

Sometimes, the series isn’t included on longest-book-series lists because many volumes are published in magazine form. But the word count for each story amounts to a novella.

First Published: 1961

Number of Books So Far: Over 5,000

Fear Street

Written primarily by R.L. Stein, Fear Street is a long-running book series for teenage audiences. 

The stories take place in the fictional town of Shadyside, and one of the foundational premises of the books is that a family who moved to the area after the Civil War was affected by a Puritanical curse.

Sometimes, the books feature paranormal elements; other times, the teenagers simply solve murders.

There are two series under the banner: Fear Street and New Fear Street. The first has 51 volumes, and the second has 4.

First Published: 1989

Number of Books So Far: 55 (between the two series)

Long, Tall Texans

Are you a fan of romance novels? If so, Long, Tall Texans may be your perfect book series! As the name suggests, the titles are about people falling in love with sexy men from the Lone Star state. 

Written by New York Times bestselling author Diana Palmer — aka Susan Spaeth Kyle — the series comprises 54 books and novellas.

If you enjoy engaging stories about “manly men,” check out Palmer’s series. They’re fun and steamy — the perfect escape from real life.

First Published: 2017

Number of Books So Far: 54

The Hercule Poirot Novels

Though they’re not typically included on most lists of the longest-running book series, we’re adding the Hercule Poirot stories to ours. After all, characters and situations are woven throughout all the tales, even though each title can be consumed independently.

From the mind of the incomparable Agatha Christie, Hercule Poirot is a fussy and brilliant Belgian detective who solves crimes among the British aristocracy and its far-off colonies.

As is the case with most of Christie’s stories, the Hercule Poirot series is rooted in traditional mystery tropes.

First Published: 1920

Number of Books So Far: 33 novels, 2 plays, 51 short stories


Also known as the 1632-verse or Ring of Fire, the 1632 book series chronicles an alternate world history. A time-travel epic, the premise is that an entire West Virginian town is transported back to 17th-century Germany during the Thirty Years War. 

Structurally, the series is divided into several threads, including (but not limited to) the Naval, Russian, South European, and Americas threads.

Author Eric Flint conceived of the series, but other writers have contributed over the years. 

First Published: 2000

Number of Books So Far: 90 (including anthologies)

More Questions About the Longest Book Series 

Do you still have more questions about the longest book series published to date? Well, you’re in luck because we’ve got answers to commonly asked queries.

How Many Books Are in the Longest Book Series?

It’s difficult to pinpoint the longest book series ever published because people use different criteria. Some folks believe it should be counted by the number of volumes, and others think word count matters most. Related short stories and articles are also considered in some counts.

All that said, most book nerds cite the Guin Saga — initially written by Kaoru Kurimoto and subsequently continued by various authors after she died in 2009.

Currently, it weighs in at 171 volumes and includes a combination of books that stick to the main storyline and over two dozen side-story editions.

What Is the Longest Single Author Book Series?

The Guin Saga also takes the top prize in the longest single-author book series ever because Kurimoto wrote the first 147 herself, in addition to other related manga stories. Other long book series penned by a single individual include:

  • Discworld series by Terry Pratchett
  • Malazan Book of the Fallen by Steven Erikson
  • The Dark Tower by Stephen King
  • The Saxon Stories by Bernard Cornwell

What Kids Book Series Has the Most Books?

The Baby-Sitter’s Club is widely considered the longest book series for kids, with over 200 volumes if you include the spin-off series. 

Investing in a book series can be highly rewarding, and for aspiring writers, it’s a great way to study detailed character and world-building development. And remember, no rule says you must only read books from a collection you start. If you tire of a particular world, put it down and jump into another novel. The series will be waiting for you when you decide to return.

Happy reading!

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