The chapel in the chancel (Cappella Maggiore) is a prime example of High Gothic. The frescoes are by Agnolo Gaddi (1380) and tells the story of the Legend of the True Cross that the church is named after.
The painted cross is by the Master of Figline while the polyptych is a recomposition: the Madonna is by Niccolo Gerini while some of the Doctors of the Church are by Giovanni del Biondo.