The British Army Basing Programme has been going on for more than seven years.
The £1.8bn programme was put into action to allow almost 100 British Army units to disband or relocate from Germany.
It has seen the construction of more than 1,000 family homes, and 4,500 single-living accommodation spaces, hailed as "really great examples of modern construction... fit for a 21st century Army".
Existing sites have also been refurbished, including those at Catterick, Tidworth, Larkhill and Bulford.
Salisbury Plain now has more than 900 new homes, as well as dozens of new workshops and garages, messes, regimental headquarters, gyms and sports pitches, as well as road improvement schemes being carried out.
Catterick, meanwhile, is now ranked as a 'Super Garrison' and, spanning 2,400 acres, is officially the largest British Army base in the world.
Improvements in North Yorkshire include the creation of additional bed spaces, and new facilities off base in Catterick, like new shopping complexes and leisure centres in the area.
General David Southall, Director of Army Basing and Infrastructure, spoke to Forces News in December about the Army Basing Programme and its significance.
What is the Army Basing Programme?
He explained the programme was set up to enable the return to the UK of 20,000 service personnel from Germany.
Watch: A look at some of the big changes on Salisbury Plain.
"It’s completed against a Government commitment made in the last Strategic Defence and Security Review, for the repatriation of something close to 100 Army units, to relocate them, reconfigure and re-role them," he said.
£1.8bn has been invested in the entire rebasing programme and the investment will save defence "about a quarter of a billion a year", Gen Southall added.
He also added that "most importantly", the Army Basing Programme was also aimed at improving the "living experience" and "operational capability" while also "delivering a more sustainable estate".
What were the priorities when bringing personnel and families back from Germany?
The Director Army Basing and Infrastructure explained that one of the key priorities was to ensure a "smooth and seamless transition" for the units and their families as they returned to the UK.
"We had a fixed timeline to deliver," he said.
"Those units and their service personnel had a day job to do, so we needed to give confidence and commit to a moving window."
One of the other necessary aspects of the programme was the need to guarantee enough housing for military families, as well as make sure relevant facilities such as schools and medical and dental facilities were "in easy reach for all".
Watch: What makes Salisbury Plain's facilities an 'all-round package'?
"So, really important that we delivered the right community in terms of new Army basic footprint in [the] UK to enable operational capability."
How many new homes and facilities had to be built?
The £1.8bn Army Basing Programme saw the construction of 1,475 family houses.
"We also built just shy of 4,500 single-living accommodation bed spaces [with] en-suite rooms for our single soldiers," Gen Southall added.
The newly built housing facilities are, according to the Director Army Basing and Infrastructure, some "really great examples of modern construction, modern building, purpose-built bespoke homes for our wounded, injured and sick, and modern standard homes fit for a 21st century Army".
General Southall also said it was "critical" to ensure that they built "one integrated community" and that working alongside councils and other organisations such as the Army Welfare Service and the Army Families Federation was "really important".
Among the sites transformed are Tidworth, Larkhill and Bulford.
Salisbury Plain now has 917 new homes, plus 54 workshops and garages, 22 messes, 13 regimental headquarters, 12 gyms and sports pitches, all newly built.
There have also been 14 road improvement schemes.
Watch: Inside Catterick's 'Super Garrison'.
Improvements at Catterick's 'Super Garrison' include the creation of 120 junior ranked bed spaces, with an increase in the number of troops has also meant new facilities off-base, with both personnel and civilians benefiting from benefiting from new shopping complexes and leisure centres.
What have been the biggest challenges of the Army Basing Programme?
The Army Basing Programme proved to be challenging at times, considering the scale and magnitude of the programme and projects.
The "pretty tight window" to rebase service personnel and their families also proved challenging, Gen Southall said.
"It [was] really important that we hit the spot to make sure that we didn't affect families in terms of pupils' schooling," he said. "We didn't want to disrupt the normal family way of life."
More recently, the coronavirus pandemic also played a role, impacting the "tactical and operational level" of some of the unit moves.
"Our working relationship with our key stakeholders, with the service families that we support [and] with the councils, I think, has enabled the moves to go as smoothly and as simply as we could expect," Gen Southall added.