Mare Frigoris (the "sea of cold") is located just north of
Mare Imbrium, and stretches east to north of
Mare Serenitatis. The mare is in the outer rings of the
Procellarum basin. The basin material surrounding the mare is of the
Lower Imbrian[?] epoch, while the eastern mare material is of the
Upper Imbrian[?] epoch, and the western mare material is of the
Eratosthenian[?] epoch.
The dark circular feature just to the south of Frigoris is the crater Plato.