Constructed in 1807, Castle Williams is a historically significant, circular fortification of red sandstone and brick. Standing on the northwest point of Governors Island, it is a prominent landmark of the New York Harbor. It was part of a system of forts designed and constructed in the early 19th Century to protect New York from attack. Castle Williams is on the National Register of Historic Places and is managed by the National Parks Service as part of Governors Island National Monument.
MPG worked closely with the National Parks Service to develop and implement the masonry restoration scope of work and procedures. The restoration work included unit replacement of red sandstone, stone dutchman repairs, patching, sounding and scaling of the stone façade, structural stabilization, lintel replacement, repointing and masonry cleaning.