'Twin towers' of up to 15 storeys high could be built on Station Square, the gateway to Milton Keynes.
The idea is one of three options unveiled by Milton Keynes Development Partnership, which aims to transform the land outside CMK rail station into a "destination" to put the city even more on the map.
All three options involve building on the civic square, which currently houses MK's main bus stops, public space and landscaped areas.
MKDC's proposals were displayed in Middleton Hall this month. Some of them involve banishing buses, filling in underpasses and mixing pedestrains with traffic on Elder Gate.
Option A is to build a low-rise structure over a main pedestrian route in the middle of the square, leaving most of the open space and access arrangements as they are.
Option B is to build a four-storey building on around half of the open space. It also removes all cars and private hire taxis and shifts all the bus stops out of the square over to the old Bus Station.
Option C proposes filling most of the public space in the square with four and 15-storey buildings - including two 'twin towers'. Cars and private hire taxis would file to the back of the station, and underpasses would be filled in beneath Elder Gate.
All the options have invoked fury from campaign group Xplain.
Linda Inoki, founder of Xplain, said: "I went to the exhibition in Middleton Hall and was furious to discover that MKDP has ignored the results of recent stakeholder workshops and is clearly angling for large-scale, infill development in Station Square. And their transport proposals are a total nightmare. "
She added: "MKDP, as the Council's land-holding arm, is supposed to take the long view of developing Milton Keynes, but they're acting like reckless heirs, desperate to sell off the family silver.
"They already own empty development sites all round the square, so what's their game With MK set to double in size, it's vital to reduce congestion and leave space for new transport services in and around this crucial transport hub.
" Xplain is all in favour of sensible and imaginative options to improve access and and add landscaping, seats, fountains or whatever to make the square more attractive - but the last thing we need is to fill it up with tower blocks."
Xplain says Station Square is the main transport interchange for a fast-growing conurbation, and therefore any improvements must flow from that.
Linda said: " Station Square is the last remaining civic square in CMK. All the others have been sold off. If this great open space, with its fine Modernist architecture, and all its flexibility and potential for the future, is sacrificed for more offices, shops and flats, where else will people be able to gather, and even protest, against the short-sighted greed of our lords and masters?"
MKDP's 35-page consultation document can be viewed here.
A Milton Keynes Development Partnership spokesperson said: “We welcome all feedback. The three potential options displayed at the exhibition received many positive responses and comment from the public.”