Horizon in the Middle of Nowhere

Kyoukai Senjou no Horizon (officially translated as Horizon in the Middle of Nowhere) is a set of school fantasy light novels by Minoru Kawakami, with an anime produced by Sunrise and a manga in Dangeki Daioh.

In the far future, humanity abandoned the devastated Earth and moved to the upper world of Tenjo. After war broke out, Tenjo and the laws of causation collapsed. Humanity was forced to return to the Earth, which had become uninhabitable except for an area called the Divine States. The Divine States were too small to accommodate all of humanity, so they duplicated the area and created a parallel world called the Harmonic Divine States. In order to once more reach Tenjo and rebuild the laws of causation, the Testament Union began attempting to rebuild history starting from 10,000 B.C. When the reproduction proceeded to 1413 A.D., a war broke out in the Divine States, and the Harmonic Divine States fell back onto the original world.

In the end, the humans living in the Harmonic Divine States lost their land and invaded the Divine States, which they renamed the Far East. The people of the Far East surrendered and the land was divided by the invaders. They tried to resume the reproduction of history, but the update of history was stopped in 1648 A.D., and the rumor rose of an impending apocalypse. Meanwhile on the floating city Musashi, students and their instructors prepare for war; A war that will determine the fate of the world...

There's also Owari no Chronicle, another series of Light Novels written by Minoru Kawakami before Kyoukai Senjou no Horizon, it's a loose Prequel to this series, also known for getting heavier as it went on running.

Aside from its (in)famous heavy nature, the novels are known from using a rather unsual numbering for its books; there are 10 books as of 2011, but it counts as 4 Volumes, that is: Kawakami uses more than one book to amount a Volume, ex: Volume 1 is two books long, Volume 3 is three books long. The system seems to be [2 books = 1 Volume] or [3 books = 1 Volume], as Kawakami has followed these two patterns strictly.

All of it is part of a chronicle, divided in 6 stages:
 * FORTH is the current world.
 * AHEAD is the setting for Owari no Chronicle: a developing futuristic society.
 * EDGE is when mankind could travel, but leave the Earth-That-Was. The discovery of a fuel from AHEAD allows for further development.
 * GENESIS is the stage when the world ends and a time where Technology Marches On and FORTH is all but forgotten. This is when the anime takes place.
 * OBSTACLE is when the world rebuilds and destroys itself.
 * CITY is the when all the technologies developed from OBSTACLE come together.

The anime 1st Season began airing Fall Season 2011, with the manga starting publication in September, 2011. The anime 2nd Season is set for Summer Season 2012.

Baka-Tsuki has a translation project for the Light Novels.

Note: Some spoilers for the light novels are here!

Kyoukai Senjou no Horizon provides examples of:

 * Absurdly Powerful Student Council
 * Action Girl: Most of the girls, especially Makiko Oriotorai.
 * All-Star Cast
 * All Men Are Perverts
 * Compressed Adaptation: The first season covers the entirety of volume one, which is actually two books from the light novels; it leaves no major event behind, but it excludes and compresses lenghty elements like conversations between minor characters and world exposition.
 * Cool vs. Awesome + Disney Acid Sequence + What Do You Mean It Wasn't Made on Drugs? = WHAT: Episode 9 showcases the fight between Futayo Honda and Kimi Aoi in an Acid Trip Dimension where Futayo uses her Slicing Dragonfly spear and Kimi simply utilizes dancing. All of this is done to a club house remix of P-01s' Leitmotif. Definitely much better than it sounds.
 * Defeat Means Friendship:.
 * Doorstopper: While the series currently has 10 light novels, the novels aren't that "light" as you can see here.
 * For a quick comparison, all books that composes the Lord of the Rings amounts to 1178 pages; the second volume of Kyoukai Senjou no Horizon (Shita Chp. ) is 1152 pages long.
 * Duck Season! Rabbit Season!:.
 * Emotionless Girl: All automatons, given they're really machines,.
 * The End of the World as We Know It: GENESIS
 * Fan Service: The entire female cast.
 * Four Is Death: GENESIS is time period four.
 * Gainaxing
 * World of Buxom
 * Hair of Gold: Margot Knight,.
 * Hide Your Lesbians: Averted; Margot and Malga Naruze are explicitly Lipstick Lesbians.
 * Hot Chick with a Sword: Makiko, Futayo and a few others.
 * BFS: And the swords are huge.
 * Hot Shounen Mom: Kazuno and . Depending on how you see it, Mrs. Aoi, too.
 * Humongous Mecha: Gods of War; while typically fielded by the Testament Union, Naomasa of the Engineering Club at Musashi Ariadust Academy has fixed up an old one for her personal use.
 * Invocation: "Judge" and "Tes" are variants: they're used as a confirmation of an action, such as responding to a question or confirming an order from authority, much like the Japanese "Hai" is used as a formal "Yes".
 * Kill'Em All: Averted in episode five. While, no harm is performed on the public since   have already left the area.
 * Like Cannot Cut Like: In episode five, during  canceled each other's attack because.
 * Loads and Loads of Characters
 * Magical Girl Warrior: Every single woman; how much "mage" or "warrior" there is depends on the person and their abilities.
 * Magitech
 * My Greatest Failure: Weaponized by, which forces anyone touching it to relive their greatest sin, and, unless they manage to completely deny it, disintegrates them.
 * Older Than They Look: Primarily Choujuzokus (長寿族), a race of people who can live for few thousand years and easily distinguishable by their pointy ears..
 * Also, automatons do not age, so Kazuno, Musashi and the other ship captains are this.
 * Rapunzel Hair: Many of the women; not only are they lengthy (with some going all the way down to the ankles) but they're plenty voluminous, too.
 * Scenery Porn: Even the Conspicuous CGI looks amazing.
 * Schizo-Tech: The series blends modern (and extremely advanced, futuristic) technology with 13th-16th century Japanese architecture.
 * Sensual Spandex: Clothing of choice in the future.
 * Seven Deadly Sins: Crops up in the form of the 9 Mortal Sin Armaments. According to Motonobu Matsudaira,.
 * Shout-Out: Nate Mitotsudaira -- "Who exactly do you think she is?"
 * While held prisoner by the K.P.A. Italia, P-01s reads a magazine about metal songs and style. The metalhead on the cover is a Lawyer-Friendly Cameo of Krauser II from Detroit Metal City.
 * Spell My Name with an "S": Minor case regarding Nate's (or "Neito's") correct romanization of her name: while The Anime Network uses the latter, the original novel spelled her name in unadulterated English using the former.
 * Theme Naming: As the current date being reproduced is during the Sengoku Era, many characters have names either reminiscent or precisely those of important players in the era.
 * The Verse: Minoru created his own world in his books; they're divided in FORTH, AHEAD, EDGE, GENESIS, OBSTACLE and CITY. Kyoukai Senjou no Horizon is part of the GENESIS saga, his previous work, Owari no Chronicle, is part of the AHEAD saga.
 * What Do You Mean Its Not Symbolic: The anime likes to throw Christian symbolism akin to Neon Genesis Evangelion. "Judge(ment)", "Tes(tament)" and "GENESIS" are but a few, but episode five may remind you of End of Evangelion's own symbolism.
 * Winged Humanoids: There are a whole race of them, it seems. Margot and Malga are the recurring examples.
 * World of Badass
 * World of Badass