Which city was the first to use fire marks on covered structures?

Philadelphia is recognized as the pioneer in using fire marks on covered structures. Fire marks were metal plaques displayed on the fronts of buildings to show that property owners had purchased insurance coverage for fire damage. This practice emerged in the early 18th century, primarily to help identify insured properties in case of a fire emergency. Firefighters would look for these marks on buildings to determine whether they were responding to a fire at an insured location, allowing them to act accordingly.

In Philadelphia, the establishment of the first fire insurance company and the subsequent introduction of fire marks helped standardize how property was insured against fire risks. This system played a crucial role in developing early firefighting and insurance practices, ultimately influencing other cities to adopt similar methods.

As a note, while cities like New York, Boston, and Chicago also developed their firefighting and insurance systems, it was Philadelphia that set the precedent with the implementation of the fire mark system.