Title 34 of the United States Code, which had been empty since 1956, is empty no longer.
As of September 1, 2017, new Title 34, Crime Control and Law Enforcement, contains editorially reclassified sections of Title 18, Crimes and Criminal Procedure, Title 28, Judiciary and Judicial Procedure, and Title 42, The Public Health and Welfare. No statutory text was repealed or amended through this reorganization.
Title 34 is now home to the Omnibus Crime Control and Safe Streets Act of 1968 (Pub. L. 90-351), and the Violent Crime Control and Law Enforcement Act of 1994 (Pub. L. 103-322), among other laws.
See the announcement from the Office of the Law Revision Counsel here and the list of former and new classifications here.