Vatican Hill
Since long before the founding of 
Christianity, one of the hills on the side of the 
Tiber opposite the traditional 
seven hills of Rome has been called the 
Vatican Hill (in 
Latin, 
Vaticanus Mons).  It may have been the site of an 
Etruscan town called 
Vaticum.
It has for some centuries been the locus of the headquarters of the Holy See and, since 1929, that of the State of the Vatican City.