Back in 1997, it was a shiny new building on a new development.
And 20 years on, despite a much changed daily work schedule, the BT calls centre at Doncaster Lakeside is still one of the borough's biggest employers, and is set to take on more staff.
Thousands have passed through the doors of the vast building since it first opened up, and some of those who were there on day one are still there.
Now there are 700 working in what looks like a vast aircraft hangar, which is the size of four full sized football pitches. But under the firm's plans to switch staff from India to the UK, that figure will rise with another 100 to be recruited over the next six months.
When the calls centre first opened in 1997, its staff were ringing round customers offering them telephone services such as the Friends and Family discount scheme, or call minder phone message service.
But two decades has changed the landscape of communications, and now staff are handling calls about things that either did not exist 20 years ago or were much less widespread, such as BT Sport, BT television, mobile phones, and broadband.
The 700 staff work from a hall which has 900 seats, working in shifts.
The firm celebrated its 20th anniversary with a giant cake and a visit from BT Sports football pundit Robbie Savage, who talked to staff on the workfloor and posed for dozens of selfies.
He said: "The staff do a fantastic job here."
The centre handles nearly 2.7 million calls a year.
It has also been used for charity telethons, such as Children in Need and Red Nose Day, with around 120 volunteers giving up their time to answer phones each time. Even Pudsey Bear in his famous yellow spotty attire has visited.
In 2015, Doncaster was also chosen as the base for a team of highly trained advisors to look after more vulnerable customers.
These customers may have a serious illness, such as dementia, or a physical or mental disability, which require advisors to have specific knowledge and understanding of how best to help them.
Doncaster was chosen because of the wealth of expertise and experience among the workforce.
One who recalls the early days is Deborah Anderson, now general manager for Doncaster, sales retention.
She was sent down to Doncaster, seconded from Glasgow, to run training sessions ahead of the opening, at High Melton College.
She said: "They were brilliant Yorkshire people, who were so enthusiastic, and took the jobs really well. I stayed here for three or four weeks, and then was moved on to Newcastle.
"There are great people in the Doncaster area and I want them to see BT as a a good career.
"We are currently moving 90 per cent of out calls centre jobs back to the UK, because that is what our customers want, and we've been public about that. We have taken on 65 in the last six months. Recruitment is ongoing with around 100 further positions set to be filled in the next six months. This includes around 30 apprentice roles."
Remembering Day One
Michael Januszkiewicz has been with BT at Lakside since day one - and the job has led to more than just making a living.
His job has also shaped his personal life. In January 2003 he went to support a new campaign at the firm's Glasgow contact centre where he met his wife, Lucy. She
moved to Doncaster and they married in September 2005.
"In the years since, we have had four beautiful daughters so as well as providing me with a long-term career, I can also thank BT for that,” he added.
Michael joined fresh out of McAuley School sixth form aged 18 as a telemarketer taking sales calls.
At the time he was juggling his calls centre job with another role - he was also working for Doncaster Rovers as Donny Dog, the club mascot. It involved dressing up in the mascot's furry costume and interacting with fans. He held the role when the club where playing non league football.
He now designs and delivers training courses across BT, training both new and existing advisors as well as new managers and other trainers.
Michael said: "I came to see what it was like, and its ended up with me being here 20 years! Back then I saw that there was a global brand coming to Doncaster and applied for a job.
"I arrived in this corporate environment, with all the PCs still wrapped up. I had my own PC and phone, and I felt like I had grown up.
"I remember there was music being played here. Sunchyme by Dario G was being played all the time. Every centre had a theme and mine was centre seven - our theme was Men in Black. Some of the special moments here have been fancy dress themes.
"There was no broadband - it was selling phone lines and things like call diversion."
He said there was a lot of competition now, and he was proud that BT had managed to get a lot of high profile sports onto its sports channel.
Michael is not along in his long service. Chris Beresford, from Bessacarr, has also been there 20 years.
The 62 year old started as a sales advisor in centre four. She remembers being trained up by trainers using blackboards at Hall Cross School before the calls centre first opened.
After four weeks in the classroom, staff finally logged on at the centre. She remembers staff often headed to the Yates Wine Bar in Doncaster after they finished work.
Latest wave of staff
Among the most recent to arrive at the site is Becca Taylor. The 22-year-old started in September.
She applied to BT after spending the rest few years working in restaurants, which is described as physically demanding. She wanted a job where she would still be talking to customers.
"I still get to make people happy and have contact with them."
She said it was very different from the calls centre stereotype of people working with scripts.
"There are no scripts," she said. "You can put your personality into how you project yourself, how you introduce yourself and how you feel comfortable speaking to people. It means people don't feel like they're talking to a robot.