The Better Archway Forum (BAF) claimed that the competition, launched this morning, will aid its bid to block council-backed proposals being worked up for the vast 2.9ha site.
BDP was commissioned by the local authority, the London Borough of Islington, last August to design a masterplan for the neglected area.
But after becoming 'frustrated and disillusioned' by the consultation exercise, the BAF has now decided to launch its own search for a design solution.
The group is already working with a number of architects, including Farrells, to work up a design code.
'What we want to see from the competition are key thoughts which could make a difference,' Simon Kaufman of Farrells said.
'We aren't necessarily looking for fully worked up schemes. The winner might be an overlooked detail which could prove the tipping point for a scheme, or the outline for a new approach which isn't yet in the mainstream.'
For further information, visit www.betterarchway.info