Amsterdam Castle, also known as the Amsterdam Armory, located at 49 Florida Avenue at the intersection with Dewitt Street in Amsterdam, Montgomery County, New York was built in 1895 by Isaac G. Perry in the castellated Late Victorian style as a National Guard Armory for the 46th Separate Company of the New York Army National Guard.

[3][4] The armory was decommissioned in 1994 and purchased by the Diana family from the State of New York in 1995.

In 2005 the Phemister family purchased the building, and continued the extensive renovation, utilizing green building techniques in addition to creating a new residence wing, a billiard room and three new bathrooms.

The property is currently in use as a private residence, bed and breakfast and distribution facility.

Originally constructed with 18" brick walls, the Phemister family's extensive renovations rebuilt the interior with separate environmentally friendly building materials including low-volatile organic compound paint and repurposed wood.