Developers behind plans to build the biggest scheme, a new Stadium for Cornwall, now aim to start next summer after the Government decided not to call in a planning application for the site at Langarth, near Truro.
Inox Group and Henry Boot Developments plan to raise funds to build the 10,000-seat regional stadium from a mixed-use development at nearby West Langarth, including a supermarket and housing.
The £20m stadium will provide a home for rugby side, the Cornish Pirates, as well as other sporting facilities and retail.
Cornish Pirates chairman Ian Connell said: “This is great news and provides the opportunity at last to make S4C a reality.
“People across Cornwall who have consistently supported this project will be delighted.
“For The Cornish Pirates we can now start to plan for August 2017 and playing in a world class facility in Truro.”
The stadium partners now need to complete the legal section 106 agreement with Cornwall Council and once completed, outline planning consent can then be issued.
Truro City Football Club have also announced that the communities secretary has waved through plans for a commercial scheme, needed to help pay for their more modest 6,000 seat stadium.
The club wants to move to the Silver Bow site on the outskirts of the city to allow their current Treyew Road ground to be turned into a retail park.
The club said directors would be meeting developers Helical Retail immediately to press ahead with plans for the new stadium.