Grosseto ...?

In Maremma?
Nice and rural. The land of the Italian cowboys.
Lots of pretty small towns to visit. Also the most beautiful coast of Tuscany.
https://www.borghiditoscana.net/en/category/province-of-grosseto/
https://www.tuttomaremma.com/en/

si, grazie Roberto

Nice area. Grosseto itself is a pleasant little city, and there's lots within driving distance. To the south, Pitigliano is wonderful for its setting, its Jewish history, and the fantastic Etruscan sacred ways (Vie Cave). Sovrana I thought was too precious, but run-down Sorana was fun to explore. To the north, Populonia and the Etruscan tombs are mind-blowing - 4,000 to 8,000 years ago!

The Etruscan Vie Cave are really interesting for hikes. And if you're in to hiking, check out Parco Regionale della Maremma / Uccellina. It's accessed from Albarese, near the coast just south of Grosetto. There's a bus that runs from the town near the visitors center to the beach if you're not so much into walking. Or you can hike up the hill to the ruins of a medieval abbey, and then down the mountain and through some umbrella pines (or along the beach if your legs are up for it) to catch the bus back to Albarese.

Scansano is supposed to be a nice place with good food, although I didn't get a chance to see it. And there's the Terme di Saturnia (thermal baths). Not as warm as I thought they'd be but still nice considering I went to the free area. There are others as well.

I assume you'll have a car? There might be buses between some areas, but unless you're staying for some time, probably not worth the time/effort. It is a lovely area though, and even though some places (Pitigliano) get tour groups, it's nothing like in the major tourist areas.

This fall I quite enjoyed driving and sightseeing around Pitigliano, Saturnia, and Populonia (good swimming there). In that region, albergolaconchiglia.it in Porto Ercole was our friendly, family-run 2-star hotel. There are also lots of agriturismi.

We stayed in Grosseto as our "non-touristy" location on a trip to Italy. (I always like to pick one place that gets us away from the tourist crowd and for a little adventure!) We stayed inside the medieval walls of the town at Grand Hotel Bastiani, a charming hotel with old style elegance and a wonderful breakfast. While we were there, we found out they were having a special Notte Musica or night arts festival. We enjoyed hearing the local choir in the cathedral, a fun gypsy (don't know how else to describe it) sing & clapping set of songs, kids performing dance routines, art displays, some excellent guitarists, and their historical museum was open for free. We really enjoyed spending an evening with so many locals! We never heard any other English-speaking people while we were there.

For transportation, we took the bus from Siena, and took the train to Rome.

I shouldn't say it, but it was my favorite area so far! The perfect combo of inland hill towns and nice coastline. We are nature lovers, so we spent a lot of time in the Maremma/Ucellina park. The Etruscan sites were fascinating. Only Pitigliano (and the hot springs at Saturnia) seemed to have mass tourism, but I am sure the coast is mobbed in summer. In May we found it idyllic.

Thank you for the wonderful suggestions. This is just what I was looking for. I have found a place to stay in Porto Santo Stefano that was suggested and I am thrilled.