Of the stunning Tuscan cities, Florence, Lucca and Pisa are wow but are relatively formal / modern / a little commercialised (especially Florence), whereas Sienna was my favourite as it had such a higgledy piggledy, older vibe to it. Roads going in all directions across the 17 flag-drenched historical districts (Contrades) with just a generally more medieval feel (the reason is that plague hit Sienna which led to Florence winning their war and the collapse / evacuation of Sienna ultimately very few modernising works done, hence the city is so well preserved), and, of course, the wow Piazza del Campo (God knows what it must be like during the bi-annual horse race, it must be insane). Don’t miss Sienna from a Tuscany itinerary, it is the 🌟