Cosona is only reachable by means of own transportation. 
The nearest urban locations equipped with supermarkets, banks, post offices, pharmacies, newsagents and weekly outdoor market are Torrenieri (less than 10 minutes’ drive), Pienza, San Quirico, Buonconvento (around 15/20 minutes drive). 
The closest airports are: Florence (140 km), Pisa (160 km), Bologna (220 km) and Rome (240 km). 
The closest train stations are: Chiusi-Chianciano Terme (46 km) and Buonconvento (17 km). 
The nearest hospitals are Nottola in Montepulciano (24 km away) and Le Scotte in Siena (48 km). 

How to reach Cosona by car.

If you are travelling from the north:

Take the A1 motorway toward Florence. Exit at Firenze Impruneta. Follow the highway Firenze-Siena toward Siena, exit at Siena Sud and proceed for Buonconvento-Roma. After Buonconvento continue toward Rome and exit at Torrenieri. Go through the town, pass the railroad and climb a series of curves (about 1.5 km). Then take the bend to the left for Cosona: you will find the Villa after travelling for 4.5 km on a dirt road (drive with caution).

If you are travelling from the south: 

Take the A1 motorway toward Florence. Exit at Chiusi-Chianciano Terme. Proceed in the direction of Chianciano, Montepulciano and Pienza. At Pienza follow the signs for San Quirico D’Orcia. About 1 km outside Pienza turn right on a paved road, following the signs for Cosona.
After about 5 km turn left on a dirt road, keep following signs for Cosona, which you will reach after 5.5 km of dirt road (drive with caution).

GPS Coordinates:
Latitude: 43.10768029392753
Longitude: 11.601288914680481