Keys in heraldry can signify open-mindedness (or, less often, closedness) and is a symbol of the power of Petrus or hence of other high dignitaries of the Roman Catholic Church.

The crest of the town of Ladenburg, once as a graffiti, once as a relief on the town gate. It refers to the diocese of Worms but also signifies Ladenburg having received its town charter.

Weekly Prompts Weekend Challenge: Key

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