Help with a book title

[Pix6]

I am trying to get the title of a book I can very vaguely remember ( good eh?). I think ( even better!) it has clans of vampires in it, ones who live on the dark side of a planet and ones who live on the light side. The two sides of the planet are divided by a huge range of mountains. The ones on the dark side live in a huge ancient crumbling tower and the higher you live up the tower the more powerful you are. I think the dark side might be ruled by a female vampire...anyone??

[LeMarchand]

Sounds like the Vampire World series by Brian Lumley: Blood Brothers, The Last Aerie and Bloodwars. These are in turn, part of a larger series, the Necro Saga. See here for details: http://www.brianlumley.com/necroscope/ .

[Pix6]

LeMarchand, wow brilliant, yes the book I read was a Harry Keogh as the Necroscope, fab - I am off th get the sequel(s)