Rome's light, season by season
At 41.9° N, Rome runs from about 9 hours 10 minutes of daylight in December to 15 hours 10 minutes in June. Summer sunsets near 20:45 CEST fill the long Roman evenings; winter brings soft, low-angle light through the middle of the day — the reason the city's ochre walls photograph so well off-season.
The Rome meridian quirk
Rome sits almost exactly on the old 12° E meridian — locally solar noon matches the clock better than almost any capital in Europe, landing between 12:10 and 13:10 depending on DST. Trust the golden-hour windows for the Tiber and the domes: the western horizon past the Gianicolo hill is clean, and the calculator's times line up with what the sky actually does.