Is Montalcino worth a day trip from Siena?
The town of Montalcino is tiny. It's all about visiting the wineries in Montalcino for us. Brunellos.
It's true, as the previous poster noted, that Montalcino is a tiny town. However,it's a good place to have a nice lunch accompanied by some Brunello. You can spend half a day there and the other half in Montepulciano or Pienza.
As Rosalyn said, combined with Montepulciano, it makes for a good day trip. The Brunello in Montalcino is an excellent wine although pricey. I prefer Montepulciano to Montalcino. Being on the crest of a high hill, there are beautiful views of Tuscan countryside from the town.
If you go to www.fattoriadeibarbi.it you will find a very accessible winery that for 5 euros gives a very nice tour & tasting of Brunellos. They also have some good links
We much preferred Montepulciano to Montalcino. Wine is the main reason for visiting Montalcino as there is not much to see here. Pienza makes a nice stop too.
I think all three towns make a nice day trip. We spent about 3 hours in each town max (including a sit-down lunch, wine tastings, walking through the cellars in Montepulciano, etc.).
in Montalcino there is a fantastic enoteco...pierangoi. If you are in the area one of the great restaurants in Tuscany is Il Poggio. They also make their own Brunello which is top shelf
If you are looking for a hill town experience, then I would pick Piensa or Montepulciano. I thought both offered a little more for a day trip. If you want great wine, don't miss it.