Southwark Cathedral sits on the southern bank of the Thames in what is now the heart of London, but it did not begin in the heart of London. Though it is not as famous as Notre Dame of Paris, nor as tall as the Sagrada Família in Barcelona, nor as instantly recognizable as Saint Basil's Cathedral in Moscow (technically named The Cathedral of the Protection of Most Holy Theotokos on the Moat ), Southwark Cathedral plays an important role in the Callahan Chronicles . Fortunatel