Authority chiefs say the building will help rejuvenate the bottom end of Botchergate.
They also add the brick and glass-fronted HQ – which from the upper floors has views across the city – is estimated to save the cash-strapped council about £900,000-a-year in the long-run.
Decorated with colourful furniture, each floor has a kitchenette where staff can make tea and coffee.
There are also rooms and space where they can take time out for meetings, booked via an electronic system.
And for workers who cycle to work there are places to safely store bikes and have a shower when they get into work.
Council leader Stewart Young said: “About 700 staff will be using the office and there are about 500 work stations.
“We don’t expect everyone to be in the office at the same time as a lot of our workers, like social workers, are out of the office a lot.
“The idea is that people can hot desk.
“They can sit anywhere and they can work from home. It’s a very flexible office environment.
“We felt that by coming here we can rebalance the city centre and help be a catalyst to regenerate Botchergate.”
Mr Young said the new base was already having a knock-on effect for business.
“A new sandwich shop has already opened next door,” he added.
“Of course it is the private sector that will regenerate the area, not us, but it is the psychological effect that it has.
“Our workers will spend money in the local shops.”
The council has been criticised for the cost of the Scandanavian-style building.
But Mr Young says it will save money in the long term as it reduces its number of offices in Carlisle from 22 to two.
The headquarters is also representing democracy in another way.
The square outside offers somewhere where people can protest, with bollards protecting the street from the Botchergate traffic.
“We wanted to have somewhere safe for people to protest, as they sometimes do. We didn’t want them to be spilling onto the road,” said Mr Young.
Lifts take people up to the different floors, with panoramic views from the solar powered roof.
Mr Young said: “If we hadn’t moved into new offices then we would have had to find about £1m in savings from our services.”
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