They were consistently dug as limestone quarries and by the 18th century, the caving in of some of these quarries posed safety threats, so the government ordered reinforcing of the existing quarries and dug new observation tunnels in order to monitor and map the whole place.

This is an avian quarantine facility where all imported birds coming into America are required to undergo a 30 day quarantine, where they are tested for diseases including Exotic Newcastle Disease and Avian Influenza.

They were consistently dug as limestone quarries and by the 18th century, the caving in of some of these quarries posed safety threats, so the government ordered reinforcing of the existing quarries and dug new observation tunnels in order to monitor and map the whole place.

This is an avian quarantine facility where all imported birds coming into America are required to undergo a 30 day quarantine, where they are tested for diseases including Exotic Newcastle Disease and Avian Influenza.