Chapter 1: Prologue
A huge castle made of stone and steel floating in an endless sky.
That was all this world was.
It took a varied group of craftsmen one month to survey the place;
the diameter of the base floor was about 10 kilometers—large
enough that the entirety of Setagaya-ku would fit on it. Above,
there were 100 floors stacked directly on top of each other; its
sheer size was unbelievable. It was impossible to even guess how
much data it consisted of.
Inside, there were a couple of large cities, countless small towns
and villages, forests, plains, and even lakes. Only one stairway
linked each floor to another, and the stairways were in dungeons
where large numbers of monsters roamed, so discovering and
getting through was no easy matter. However, once someone
broke through and arrived at a city in the higher floor, the
«Teleport Gates» there and in every city in the lower floors would
connect, making it possible for anyone to move freely through
these levels.
Under these conditions, the huge castle had been steadily
conquered over two years. The front line was currently on the
74th floor.
The name of the castle was «Aincrad»; a floating world of battles
with swords that had engulfed approximately six thousand
people. Otherwise known as...
«Sword Art Online»
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