Built between 1861-64, to a design by Edward William Godwin. The west wing was extended 1889-92 by Matthew Holding following the original architecture. A further extension was made in 1992, but to a more modern design but still sympathetic with the original. Statues and friezes enhance the facade, the statues being mostly of monarchs who had visited Northampton. The hall holds a memorial to Lady Diana Spencer, Princess of Wales - Althorp, the seat of the Spencer family is near to Northampton.