More Hall Annex

Seattle, United States

No longer standing

Demolished or destroyed.

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More Hall Annex, originally known as the Nuclear Reactor Building, was a Brutalist concrete structure on the University of Washington campus in Seattle, completed in 1961 to house a nuclear research reactor. Designed by UW faculty members, the building featured an innovative design with large windows surrounding the reactor room, intended to demonstrate the safety of nuclear energy through transparency. Operating at a peak of 100 kilowatts thermal, the reactor functioned until its shutdown in 1988 and official decommissioning in 2007. The building was added to the National Register of Historic Places in 2009 following preservation efforts, though a subsequent lawsuit failed to prevent its demolition in July 2016, after which it was replaced by a computer science building.