* The Lord of the Rings by J.R.R. Tolkien: The classic fantasy epic, a timeless tale of good vs. evil.
* A Song of Ice and Fire by George R.R. Martin: A complex and sprawling tale of politics, power, and dragons.
* The Kingkiller Chronicle by Patrick Rothfuss: A beautifully written story told through a frame story about a legendary king.
* The Broken Earth Trilogy by N.K. Jemisin: A thought-provoking and powerful series exploring themes of climate change and societal structures.
* The Mistborn Trilogy by Brandon Sanderson: A captivating story about a group of rebels fighting against an oppressive empire.
* The Hitchhiker's Guide to the Galaxy by Douglas Adams: A hilarious and witty series about a man who gets swept up in a galactic adventure.
* The Expanse by James S.A. Corey: A thrilling space opera with detailed world-building and complex characters.
* The Martian by Andy Weir: A suspenseful and scientifically accurate story about a man stranded on Mars.
* The Culture by Iain M. Banks: A complex and thought-provoking series about a utopian society in the far future.
* The Three-Body Problem by Cixin Liu: A mind-bending and ambitious series exploring the possibility of extraterrestrial life.
* The Pillars of the Earth by Ken Follett: A sweeping story of love, betrayal, and ambition set in medieval England.
* The Nightingale by Kristin Hannah: A heartbreaking and powerful story about two sisters in occupied France during World War II.
* The Book Thief by Markus Zusak: A poignant and unforgettable story about a young girl who finds solace in stolen books during Nazi Germany.
* The Guernsey Literary and Potato Peel Pie Society by Mary Ann Shaffer and Annie Barrows: A heartwarming and charming story about a writer who discovers the power of community.
* The City of Brass by S.A. Chakraborty: A captivating blend of historical fiction and fantasy, set in a world inspired by Arabic mythology.
* The Hunger Games by Suzanne Collins: A thrilling dystopian series about a young girl who volunteers for a deadly competition.
* The Divergent by Veronica Roth: A fast-paced and action-packed series about a society divided into factions based on personality traits.
* The Raven Cycle by Maggie Stiefvater: A magical and atmospheric series about a group of teenagers searching for a Welsh king.
* A Court of Thorns and Roses by Sarah J. Maas: A romantic and action-packed series about a young woman who finds herself in a magical realm.
* Six of Crows by Leigh Bardugo: A thrilling heist novel with a diverse cast of characters and a complex plot.
This is just a small sample of the many great book trilogies out there. You can find more recommendations based on your specific interests by searching online or talking to a librarian or bookseller.