This very unique and very rare door is a perfect example of a little-known period called 'Rybism'* which was between 1210 and 1290. When I saw this door, I immediately wanted to know more so I did a little bit of research and found that it was recently discovered buried behind a wall of a palace and that it's beauty has remained intact thanks to the plaster work that covered it.
*Rybism: translated 'fishism'