The site where an atomic weapons factory once stood has been sold to two house-building companies.
Homes are now planned for the site after a retail developer backed out
George Wimpey bought the 15.8 acres of land in north Cardiff once occupied by the Atomic Weapons Establishment (AWE), and sold half to Barratt South Wales.
The firms plan to build between 330 and 350 homes and widen the neighbouring Caerphilly Road.
The factory closed after 57 years of operation in 1997. It took two further years to decontaminate the land.
The site had been ear-marked for sale to an out-of-town retail developer in 2001 but it backed out of the deal later that year.
The land, and outline planning permission for the homes, was put back on the market with an asking price of £18m but has only now been sold.
Phil Williams, of property consultant King Sturge, said: "We're delighted to have been able to secure a sucessful sale.
"The history of this site has had its fair share of twists and turns, but it has always been a prime location in the context of available development land in north Cardiff. "
The atomic weapons plant grew out of a conventional Royal Ordnance factory, which had opened in 1957.
AWE still has bases in Aldermaston and Burghfield in Berkshire, which provide Britain with nuclear war heads.