Northumberland’s long-awaited Landscape Discovery Centre and Youth Hostel at Hadrian’s Wall – known as “the sill” – will open to the public this weekend (29 July) after more than three years of development for the British heritage attraction.

designed by Newcastle-based architects Jane Darbyshire and David Kendall (JDDK), the £14.8m (US$19.4m, €16.6m) project was given the go-ahead in October 2014, with the public opening to take place during National Parks’ Week.

Replacing a 1960s-era visitor centre, the Hadrian’s Wall site has been completely redeveloped to incorporate learning facilities, youth hostel accommodation, conference and exhibition spaces, retail, a tourist information service and a local produce café with communal spaces.

The Sill is designed to be eco-friendly, meeting the highest standards of sustainability, with a target of self-generating 80 per cent of energy consumed on-site.

Featuring a living grass roof planted to replicate the surrounding natural grasslands, with locally-sourced materials used for the rest of the development, JDDK’s design incorporates the Northumbrian landscape in not only its form but also with materials used in construction.

“The Sill is the UK’s first dedicated National Landscape Discovery Centre,” said Sarah Glynn, Sill manager. “An all-weather, all-year facility, The Sill is designed to excite, inspire and enable people of all ages to understand and explore the landscapes, history, culture and heritage of Northumberland and the many other fantastic attractions in the county and beyond.

“After many, many months of dedication and hard work it’s fantastic to be celebrating the opening and welcoming the public at last.”

Northumberland National Park Authority and the Youth Hostels Association (YHA) are partners to the Sill, with the Heritage Lottery Fund (HLF) part-financing the development, granting £7.8m (US$10.2m, €8.7m) in 2015. Engineering and construction firm Sir Robert McAlpine were general contractors, with Cundall acting as planners, Glen Kemp as landscape architects and Gardiner and Theobold as project managers.

It’s thought that the new opening will greatly benefit the region, with the redeveloped centre expected to attract more than 100,000 visitors a year.