- CollectionMiscellaneous - Miscellaneous Papers
- SeriesBox 16 - Letters Sh-Sy
- FileST5 - Letters from Robert Stewart, Viscount Castlereagh
- Item1 - Autograph letter signed to William Eden, Baron Auckland, from London
- Item2 - Letter signed to Joseph Marryat, from the Foreign Office
- Item3 - Autograph letter signed to an unknown recipient, from the Foreign Office. Enclosed is an extract from a letter from Lord Liverpool to Castlereagh, dated 6 Dec. from Bath, in Castlereagh's hand
- Item4 - Autograph letter signed to 'Dear Kennedy', from St James's Square
- Item5 - Letter signed to an unknown recipient, from 127 Park Street