Here is the schedule for Florence
Masses in Latin with Gregorian chants
Firenze
S. Miniato al Monte
Via del Monte alle Croci tel. 0552342731
Daily
Winter: Vespers at 16.30
Mass at 17
Summer: Vespers at 17.30
Mass at 18
Duomo
Piazza Duomo Tel. 055 2302885
Sunday at 10.30
S. Francesco al Poverino
Piazza SS. Annunziata
Holidays at 10.30
closed August
Information - tel. 0552340917 0558544434
S. Salvatore al Monte
Via Monte alle Croci tel. 0552342640
Saturday at 18.00
(winter) - (summer)
Certosa del Galluzzo
Località Galluzzo tel. 0552049226
From 1st October to 1st Sunday of June
2st Sunday of the month at 11.00
Surroundings
Cappella Santa Trinita (Villa Martelli)
Via di Gricigliano, 52
Località Le Sieci tel 0558363068
Weekday Mass in Latin without chants at 11.45
Vespers at 18.30
Holidays Mass with Gregorian chants at 9.30
Mass with organ at 11.00
Vespers at 18.00
Monastero delle Benedettine di Santa Maria a Rosano
Borgo del Monastero, 13
Località Rosano - Rignano sull’Arno tel. 0558303006
Weekdays Mass at 7.00
Holidays Mass at 10.00
Holidays Vespers at 17.30 (in summer at 18.30)
Sunday Vespers 17.00 (in summer at 18)
I believe that the Vatican has gregorian services as well RR