Seine (French: [sɛn] ) is a former department of France (1795–1968), which encompassed Paris and its immediate suburbs. Named after the river Seine which flowed through it, it was the only enclaved department of France, being surrounded entirely by the former Seine-et-Oise department.
Its prefecture was Paris; its INSEE number was 75 (now Paris). When the Seine department was disbanded its territory was divided among four new departments: Paris, Hauts-de-Seine, Seine-Saint-Denis and Val-de-Marne.