From June 19th to 24rd, starting at 4:30 PM, an extraordinary illumination can be admired in the Hall of the Burial Urns in Castel Sant'Angelo: a Rectangle of Light that perfectly centers the niche on the east side.
The same thing happens in the morning, at 8:55 AM, when a Rectangle illuminates the niche on the opposite west side, but at that time the Castle is still closed.
The Rectangle of Light is visible only on the days of the Summer Solstice, when the Sun is high enough for its rays to enter through the splayed windows which open high in the vault. Outside, in the Courtyard of the Angel or the Courtyard of the Well, those windows have a special shape created for this purpose.
The symbolic meaning of the Rectangle of Light and the building secrets of the Mausoleum, along with its thousand-year history, are revealed in Marina De Franceschini's book, «Castel Sant'Angelo. Mausoleum of Hadrian. Architecture & Light» also in English edition.
A valuable Guide available for purchase in the Bookshop of the Castle, featuring a new and previously unpublished reconstruction of the Mausoleum as it was during Hadrian's reign.
AVAILABLE IN THESE BOOKSHOPS IN ROME
Libreria Cicerone - Largo Chigi, 1A Roma (vicino alla Galleria Alberto Sordi)
Libreria Horafelix - Via Reggio Emilia, 89 Roma (vicino al Museo Macro)Bookshop del Museo di Castel Sant'Angelo