The Witham Testimonial was built by public subscription as a memorial to Henry T.M. Witham of Lartington, a palaeobotanist and philanthropist who had strived to make provision for the medical and educational needs of Barnard Castle before his death in 1844. Hence the building, which opened in 1846, housed the Mechanics' Institute and a Dispensary for the Relief of the Sick Poor. By 1860, a large music hall had been built to the rear of the Testimonial Building, whilst the premises later incorporated several small cottages in Hall Street. Together these buildings became known as The Witham and have continued to be used by the people of Barnard Castle as a backdrop for celebration, for participation and for people to gain new experiences.
2013 marks the culmination of over 10 years work to raise money and carry out work to restore its historic fabric and make The Witham fit-for-purpose as a fully accessible modern arts venue for the 21st century. The redevelopment project has seen the original Grade II listed Witham buildings restored, and a new link building constructed between the Witham Testimonial and the Music Hall, incorporating a foyer area, café bar and toilets. In addition, Durham County Council has extended and refurbished its Library building to the rear of The Witham buildings, to include new council offices and a customer access point as well as the continued Library service.
Funding of the project principally came from Durham County Council investing over £2 million with match funding of £336,000 from the Heritage Lottery Fund (HLF) and £773,879 from the European Regional Development Fund (ERDF). The ERDF funding is part of a wider programme which has brought more than £300 million to the North East. The Witham and Library development project was led by Barnard Castle Vision, Durham County Council and The Witham Directors.