arno in luce.

cfr. Wikipedia
La Luminara di San Ranieri (vernacolo pisano per Luminaria) è una spettacolare manifestazione che si svolge a Pisa la sera del 16 giugno di ogni anno, vigilia di San Ranieri, patrono della città. Migliaia di lumini vengono posti su telai in legno (detti biancheria) che vanno a disegnare le forme architettoniche di chiese, palazzi e torri dei lungarni. Quando cala la sera, queste luci vengono riflesse nelle acque dell'Arno creando effetti suggestivi. A mezzanotte fuochi d'artificio concludono la festa.

Candlelight Festivities Luminara di S. Ranieri
This event takes place on the eve of the patron saint’s feast day (June 16) and transforms the lungarni into a phantasmagoric fairy-tale setting.
The architectural details of the palaces – windows, cornices, balconies – the parapets of the river and the bridges glow in the reflected light of over 70,000 ‘lumini’ (small glass lamps burning oil or wax) while thousands of lighted candles float on the waters of the Arno.
Sham architecture (‘machines’) and a firework spectacle at the Cittadella Vecchia make this event, which dates back to 1688, even more fascinating.
In that year (on March 25th) the urn containing the mortal remains of Saint Ranieri, patron saint of Pisa, was placed in the Cappella dell’Incoronata in the Cathedral (thereafter dedicated to the saint).
The Luminara, or better the Illumination of Pisa, as it was called around the 19th century, has been held every year since then, except for a few interruptions.
The custom of celebrating in the city with the lighting of fires, bonfires and explosion of gunpowder is documented as early as the 15th century and a real ‘illumination’ seems to have existed before its official beginnings.
On June 14, 1662, Pisa celebrated the passage through the city of Margherita Luisa d’Orleans, wife of Cosimo II, with an abundance of candles, lights and cannon salvoes.
As the centuries passed, the custom became ever more spectacular, in particular thanks to the regular use of the ‘machines’ which altered and transformed the actual architectural views along the Arno. A particularly magnificent edition of the Luminara was held when the King of Naples visited the city (june 16, 1836).
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