Number One Observatory Circle is the official residence of the vice president of the United States. Located on the northeast grounds of the U.S. Naval Observatory in Washington, D.C., the house was built in 1893 for the observatory superintendent. The chief of naval operations (CNO) liked the house so much that in 1923 he took over the house for himself. It remained the residence of the CNO until 1974, when Congress authorized its transformation to an official residence for the vice president, though a temporary one. It is still the "official temporary residence of the vice president of the United States" by law. The 1974 congressional authorization covered the cost of refurbishment and furnishing the house.