Florence ideas

Our 2 favorite museums
Bargello and San Marco
Neither will require pre booking and neither will be crowded

Visit Mercato Centrale-have lunch or dinner there

Wander the Oltrarno district
View from P Michelangelo

We loved our all day Tuscany Tour with Walk about Florence, they have an air conditioned bus that takes you to three hilltop villages, including Pisa and lunch at an organic winery (where I discovered I am not allergic to Red wine if it's organic!) and it is just a really fun day. Take a look on their website for all the details.

Me, if only a brief city visit, prefer to be in the city. I enthusiastically second the notion to take in Mercato Centrale; it's certainly not their oldest market and will have maximum tourist volume, but this is yet another terrific example of just how downright superlative Italians treat, deal, offer, provide, produce foodstuffs that makes you wish you will never accept any item less fresh and well prepared, ever, in the future. Guide tip/plug for Coral Sisk of The Curious Appetite, curiousappetitetravel.com

hey hey jjpain9989
have you been before?
withlocals.com/ florence
many different things to do, "best street food spots & drinks", "private chianti wine tour in vintage fiat"
eatwith.com
search florence, "mercato centrale and san lorenzo tour with street food lunch. take a walk in this market centrale, two stories with anything and everything to ooohhh and aaahhh at.
look under event types, cooking class, lunch/dinner in a residents house with others. "handmade pasta with anna"
discoverytuscany.com
under things to do, events calendar, october. it's harvest/festival time, see if anything going on while you're there, they are so much fun: eat drink be merry, see all the pagentry, families, walking the booths
tasteatlas.com/ bomboloni
well known fried doughnuts, go to pasticceria cucciolo on via del corso and have some treats
tuscan-wine-tours.com
super chianti tour, tasting wine, stopping for lunch at the famous butcher dario cecchini
educated-traveller.com
wine windows of florence. we saw the windows on a pedicab tour. they weren't in use but was told about them and now they have been renovated. sit down and have a glass, people watch, enjoy
your time is so short but do enjoy what there is to see and do. we love it. roam and walk around, see all the cafes, leather shops. artisan made products, souvenirs. have fun
aloha

Basilica of Santa Croce
Battistero di San Giovanni
Museo Galileo
Mercato Centrale

So many things to do right in the center of the city.

With as little time as you have, I'd spend it all in Florence. There is a lot to be seen there IF they are things which interest you; specifically Renaissance art and architecture.

If you're going to the duomo, I'd buy a pass for the duomo museum and baptistry as well, since you'll be right THERE. This is the pass you'd want unless you want to climb either the Bell Tower or cathedral's dome:

https://operaduomofirenze.skiperformance.com/en/store?skugroup_id=3006&product_id=13346#/en/buy?product_id=13346&skugroup_id=3006&bookable_y_n_a=a

Climb up (or take a bus or cab up) to San Miniato al Monte: a VERY old and important church with a great view over the city. Visit the adjoining cemetery as well. From here, you can climb down to Piazzale Michelangelo, and then further down into the city. All of this is free.
https://www.visitflorence.com/florence-churches/san-miniato.html
https://www.visitflorence.com/florence-monuments/piazzale-michelangelo.html

I'll second San Marco and the Bargello, and add Piazza Santissima Annunziata (very close to San Marco) + a look at the church of the same name.
https://www.visitflorence.com/florence-monuments/piazza-ss-annunziata.html
https://www.visitflorence.com/florence-churches/santissima-annunziata.html

Santa Croce:
https://www.visitflorence.com/florence-churches/santa-croce.html

Santa Maria Novella:
https://www.visitflorence.com/florence-churches/santa-maria-novella.html

Santa Trinita; specifically for the Sassetti Chapel:
https://www.visitflorence.com/florence-churches/santa-trinita.html

And, of course, Piazza della Signoria and Loggia dei Lanzi:
https://www.visitflorence.com/florence-monuments/piazza-della-signoria.html

Thank you all for your great suggestions! I wish we had more time in Florence. We’ve never been to Italy, so we are spending time in Rome, Assisi and Venice. We already have decided we need to return to see other beautiful cities.