The location of Hitler's remains is unknown to prevent it from becoming a fascist memorial.

The Weimar republic was the government of Germany after WW1. For reasons unknown to me it was moved from Berlin to Weimar.

Here some say it is Luke but some say it is a unknown author.

The Berlin wall has over 200,000 visits each year, but the most visited spot is temporarily unknown.

The cast of Preacher with an Unknown God - 2005 includes: Stop Big Boxes Gospel Choir as Themselves Reverend Billy as Reverend Billy Savitri Durkee as Director of the Church of Stop Shopping