The structure is characterised by a circular plan and represents an important and valuable artefact of the 16th century, whose construction is attributed to the English Cardinal Reginald Pole. The chapel recalls the form of Roman temple tombs, with walls marked by eight brick pilaster strips, with peperino capitals and stone plinths supporting an architrave on which a polychrome terracotta dome is set. Two travertine portals were sealed over in the late 1990s, as were the four upper clipei.

The project for the conservative restoration and enhancement of the Chapel included a series of interventions aimed at preserving and enhancing this important historic building. The roof was overhauled, and waterproofing was provided to ensure protection from atmospheric agents. The entrances were unsealed, and new wooden portals were made, thus restoring the original appearance of the entrance. The missing parts of the walls were rebuilt and consolidated, ensuring the building's stability. Masonry materials such as bricks and stones were cleaned and consolidated. Painted interior surfaces were preserved and restored. The floor area was also cleaned. Finally, the artistic lighting system was improved to highlight different architectural elements.