Connecticut used to be a renowned far and wide for its manufacturing, but what is less well known is that mining was also a very large part of Connecticut's industrial scene. According to the Connecticut Geological Survey in Hartford there are over 600 abandoned mines and quarries within the borders of Connecticut. The iron ore of the Salisbury District gave rise to some of the largest mines in Connecticut. The Salisbury District was not just one town it consisted of seven towns in Connecticut as well as other iron producing towns in Western Massachusetts and Eastern New York. Iron was produced throughout the district that at its peak contained twenty seven blast furnaces producing cast iron as well is innumerable forges capable of producing wrought iron for almost two centuries.
Iron itself was not a monopoly of Salisbury as the first iron furnace in Connecticut was erected in West Haven at the outlet of Lake Saltonstall by the first Governor of Connecticut John Winthrop Jr. Winthrop had been active in setting up several of the furnaces and Eastern Massachusetts including the one located at Saugus. The Saugus Massachusetts furnaces have sense been reconstructed and are now part of the National Park Service.
In 1644 Winthrop petitioned the General Courts of Connecticut for permission to erect an iron furnace in what is now West Haven at the outlet of Lake Saltonstall. In 1651 he finally gained the General Courts permission or wrecked a furnace under some very liberal terms. This was the earliest iron furnace that was located in the State of Connecticut. Winthrop’s furnace continued in production until 1678 to produce “sowes” (pig iron) and pots until the ore bed was presumably depleted. The furnace was allowed to go out of blast, and it wasn't until some 80 years later that another iron furnace was erected in Salisbury, Connecticut. In the intervening 80 years all the iron that was produced in Connecticut came from small forges.