Fountains of Bright Crimson (1999)

From the Back of the Book:

The Holy City Gone Mad

In 1099, the victorious Crusaders captured Jerusalem and then embarked on an epic frenzy of slaughter and destruction. Now, a century later, the seeds watered by that bloody harvest finally blossom. A madman stalks the nights. An ancient vampire stirs in his slumber. A holy spring weeps tears of blood. Unless someone can learn Jerusalem's darkest secret, the slaughter will begin anew.

Blood Stains the Waters

Fountains of Bright Crimson is an adventure chronicle for Vampire: The Dark Ages. It explores the greatest mystery and tragedy of Jerusalem's Cainite history - the Weeks of Blood. Now the hideous truth behind the slaughter of innocents can be told - if you are brave enough to know the answers.