Fleet Prison, former jail in London, England. Rebuilt after it was destroyed in the Peasants' Revolt of 1381, again after the great fire of 1666, and once more after the Gordon riots of 1780, it was finally demolished in 1845–46. After the 17th cent. it was notable as a debtors' prison. Fleet marriages were clandestine and irregular ceremonies performed at Fleet Prison by debtor clergymen. Although not illegal, the system was so abused that it was abolished in the reign of George II.