Castello del Nero is a prize. It is sited beautifully. It is meticulously kept. The service could not be more accommodating. The food was delicious. There is just nothing they could do better. CDN is among my best ever hotel experiences. I recommend it without qualification whatsoever.
We used CDN as base and made day trips to Siena, Cortona, Florence and Greve. All were easy drives.
The hotel staff made reservations at local restaurants they selected. The choices made were outstanding too. The staff arranged for a driver so that we would not need to worry about getting lost at night or have a DD.
There is a spa at CDN which we did not use but it seemed awfully good too.
We will likely use it again during our next trip to Tuscany.