Llanrumney Hall, the rumoured home of Sir Henry Morgan, will be transformed into a community education and sporting facility.
The decision was backed by Cardiff City directors Steve Borley and Vincent Tan and will be funded by Cardiff City House of Sport.
Renovations are now in their first phase of development, with future hopes to develop a 4G sports pitch and new changing facilities if funding will allow it.
Cardiff Council said, “The aim of the refurbishment is to keep the building relevant for new generations to enjoy.”
They also added that they would like to incorporate its historical importance and transform it into a community facility that can be used by anyone and everyone.