The prompt is not specific as "classical" favorites but so many other days catch classic rock, classic soul, etc. I fell in love with this piece -- and Tchaikovsky in general -- while learning it for the New Mexico High School All-State Orchestra in 1983 or 84.
Day 03: 1812 Overture, Op 49 / Pyotr Ilyich Tchaikovsky
Concerts at Wolftrap, Flag Day at Ft McHenry... this song reminds me of the hot, sticky days of a DC summer.