Where: Launsdorf, Austria

Start of construction: 9th Century

End of construction: 1571 - 1581

Accessible: yes

Important fact:

The castle has 14 separate entrance gates.

One of the reasons why no enemy was ever able to conquer it. They never got beyond gate 4.

The distance between gates 1 and 14

is 650 metres.

https://www.burg-hochosterwitz.com/en/