Henry Castree Hughes (29 May 1893 – 1 January 1976), known as H. C. Hughes or Hugh Hughes,[1][2][3] was a British architect and conservationist. He spent his entire career in Cambridge, where he practised architecture from 1923, latterly as Hughes and Bicknell with Peter Bicknell, and lectured in design at the School of Architecture of the University of Cambridge (1919–32). As an architect, he is best known for his Modernist buildings of the 1930s, particularly the Mond Building (1931–32) and Fen Court, Peterhouse (1939–40), although much of his output was traditional in style. He also carried out restoration work on cottages, Cambridge college buildings, and churches, including the Lady Chapel of Ely Cathedral. He was an elected fellow of the Royal Institute of British Architects.
He lobbied on issues relating to the conservation of the countryside surrounding Cambridge, and was instrumental in the foundation of the Cambridge Preservation Society in 1928.