A gasholder house is a structure built to surround an iron gasholder in which gas is stored until it is needed. Before the 1870s, most iron gasholders were constructed without a building structure, but following practices already common in the New England, gasholders houses were adopted in New York. Additionally, gasholder houses were constructed in England as early as 1825, although the mild climate made them less of an advantage. There are eleven known gasholder houses in the United States, with the structure in Troy, New York being one of the largest remaining structures of this type.