St. John XXIII was also previously buried in the same place.
Prime minister Viktor Orban went to Rome with his wife; president Katalin Novák will also attend the funeral.
Zen was elevated to cardinal by Benedict in 2006.
The bells of all Catholic churches of the 27 dioceses of Germany are expected to toll at 11 a.m. (local time) on Jan 5.
Most acts of Christianophobia in Europe can be put in the category of discrimination rather than physical extermination (for now).
The beatification of John Paul II took place on the 1st of May 2011 and he was canonised on the 27th of April 2014.
The German Pope is considered as one of the greatest contemporary theologians.