Backed by a £13.9m Heritage Lottery Fund grant, Nottingham Castle is being refurbished to draw the tourists.
The first stage will see the construction of a new visitor centre and an extension to the Ducal Palace, where Robin Hood and Rebellion galleries will be created.
The goal is that after completion in 2020 visitor numbers will more than double to 400,000 a year.
GF Tomlinson was appointed by project lead Nottingham City Council on the back of its track record in the heritage sector.
Works also include refurbishment of the Ducal Palace, with various galleries being created to showcase the castle’s art collection, and landscaping works to the grounds.
GF Tomlinson managing director Andy Sewards said: “Nottingham Castle is one of the city’s greatest treasures, with people from all over the world aware of its rich history. We understand the importance of the redevelopment of the castle and the benefits this will bring to the local economy, so it’s an honour to have been chosen to deliver such important works.”
Ted Cantle, chair of the Nottingham Castle Trust, said: “After more than five years of working with the council and having played a crucial role in the conception and design of the scheme, the Trust is pleased to be moving towards operating the site. We will now begin the process of commissioning the set-up arrangements, getting the new team and facilities in place in readiness for opening day.”