LOTR was originally written as one book and split by the publisher because large books weren't as marketable at the time.

A Dance with Dragons, the fifth ASOIAF book, looks like this...

[img]http://www.runningwithspoons.com/wp-content/uploads/2013/11/Dance-With-Dragons.jpg[/img]

...and it is 422k long; nearly as long as the entire LOTR triology.