The classic 2-Headed Eagle heraldry of the Holy Roman Empire found on a small door around the side of Montserrat, in the Catalonia region of Spain in 2006. I like the evolution of locks in evidence.
The double-headed eagle is a common symbol in heraldry and vexillology. It is most commonly associated with the Byzantine Empire and the Holy Roman Empire. In Byzantine heraldry, the heads represent the dual sovereignty of the Emperor (secular and religious) and/or dominance of the Byzantine Emperors over both East and West. In the Holy Roman Empire’s heraldry, it represented the Church and the State. - from wikipedia
