I will be visiting Italy in June. Would Siena or Florence be a better base for me? I will be there about 4 days before moving on to another location.
A lot depends on what appeals most to you. Florence is high energy, mega art big city life. Siena is more medieval, some art, more quaint, a good hub for exploring the nearby small towns. Both are fabulous--- we'll be spending four days in each in less than two weeks. If you will have a rental car Florence can be a problem because of the limited traffic zones.
FYI, after reading RS and many of the helpful postings here, we've decided to split; Florence 2 nights, Siena 2 nights. Will rent car leaving Florence for Siena.