Four horseman quest

Can someone please help me with these quest?
It is uw quest, but my question is where do I get it,and do I have to solve some other quest before in order to start this one?
I heard some really good items drops on that quest, so I'm corious.
Thanks for help!:-)

Perhaps reading something like this might help:

http://www.guildwarsguru.com/forum/s...=four+horsemen

This is why you should use the search engine...
You'll find good stuff..!

Well,I did use search engine...but at the wrong addres;-)
Anyway, really thanks for that link!