Guggenheim Museum New York

In 1959, the museum moved from rented space to its current building, a landmark work of 20th-century architecture. Designed by Frank Lloyd Wright, the cylindrical building, wider at the top than the bottom, was conceived as a "temple of the spirit". Its unique ramp gallery extends up from ground level in a long, continuous spiral along the outer edges of the building to end just under the ceiling skylight. The building underwent extensive expansion and renovations in 1992 (when an adjoining tower was built) and from 2005 to 2008.