King's began on a site adjacent to Somerset House in the Strand, still in use and still organized around the original building; the university has spread to several other campuses as well, including the Guy's campus near London Bridge, the St. Thomas' campus facing the Houses of Parliament across the Thames, and the Hampstead campus on Kidderpore Avenue, formerly the site of Westfield College, since merged with Queen Mary. The current institution is the product of the merger of King's with a number of other institutions over the years, including Queen Elizabeth College, Chelsea College, the Institute of Psychiatry, Guy's Hospital, and St Thomas' Hospital.
King's has over 17,000 students. Well-known alumni include Anita Brookner, Arthur C. Clarke, Derek Jarman, B. S. Johnson, Hanif Kureishi, Michael Nyman, and Desmond Tutu. Florence Nightingale's original training school for nurses was at St Thomas's Hospital and King's College Hospital. Perhaps the most famous scholarly research performed at King's was the work by Rosalind Franklin and Maurice Wilkins that was essential to the discovery by James Watson and Francis Crick of the structure of DNA.