The M3 line is the planned third line of the Warsaw Metro. The first section will number 7 stations and will link Stadion Narodowy with Gocà Âaw.
The first plans to construct the metro line emerged in the 1970s and 1980s, with a view to construct M3 between OkÃÂcie and Ochota with Gocà Âaw and Julianów. Later on, plans were changed, with the connection shortened to one between OkÃÂcie and Warsaw West railway station. Plans were shortened once again, with the final draft of the line covering stations from the National Stadium to Gocà Âaw.
In 2015, Warsaw city authorities planned for the construction of the M3 metro line between Stadion Narodowy and Gocà Âaw to commence in 2020. In 2018, Civic Platform's Warsaw mayoral candidate Rafaà  Trzaskowski declared, if he won the upcoming elections, the construction of the M3 metro line would begin before the end of 2023.
In May 2019, Warsaw Metro declared a tender for completion of a technical study of the route of the M3 metro line, including the construction of the Kozia Górka technical and holding station. The technical study would analyse the proposed route and the preferred location of stations of the first section of the metro line between Stadion Narodowy and Gocà Âaw.
On 26 June 2020, the results of the technical study and proposed route were published. The same day, Warsaw Metro announced that the technical study only encompassed the first section of the M3 metro line. The metro line might be extended across the Vistula and link to the M1 metro line around the Racà Âawicka metro station.
The construction of the M3 metro line formally began on 15 March 2021.