The Peter and Paul Fortress was the founding site of St. Petersburg, an imperial citadel used for tsarist pageants, elaborate masses, and Romanov burials. It was also absolutist Russia's most notorious political prison. The empire's most illustrious dissidents – Bakunin, Chernyshevsky, Nechaev, Kropotkin, Ulyanov, Trotsky – not only suffered within its walls, but also wrote novels and treatises, planned future political activities, and reimagined what it meant to be a revolutionary actor in tsarist Russia. From 1825 to 1930 the Peter and Paul Fortress was a crucial space for both Romanov political culture and its radical contestation. My project uses the tools of intellectual, cultural and spatial history to examine this site along three axes. First, the Peter and Paul Fortress as stage of the revolution: how did the experience of imprisonment become a pillar of the Russian revolutionary tradition, a site for the literary and experiential production of a radical subject? Second, as writing desk of the revolution: what accounts for the flood of texts written and distributed within this prison, and how does this "underground republic of letters" force us to rethink received notions regarding the public sphere in imperial Russia? Third, as museum of the revolution: what does the Soviet transformation of this political prison into a radical museum tell us about how pre-revolutionary dissidents contested the spaces of tsarist ritual, and how post-revolutionary Bolshevik memory politics constructed legitimizing historical narratives? Basing itself on memoirs, correspondences and tsarist prison archives, my dissertation is the first modern history of this site in any language. Examining the Peter and Paul Fortress from 1825 to 1930 leads us to new insights into the birth of the Russian revolutionary tradition; the entwinement of symbols, spaces, and subjects in political cultures of dissent; and the phenomenon of political imprisonment in European modernity.