The only reason for most visitors to go to Chiusure is not to visit the village itself, but the Abbey of Monte Oliveto Maggiore, which is up a hill a few hundred metres from the center of the village. Chiusure is about half way between Buonconvento and Asciano, on a road that goes through a unique, pock-marked (Crete senese = Sienese craters), semi-arid region, but the abbey itself is on a hill green with cypresses.
Best access is by car, and there is parking available on the hill where the abbey is situated. Note: The road from Asciano is currently closed for repairs, so take the road from Buonconvento.
It appears that service from Siena to Chiusure has been discontinued. It is possible to take a bus to Asciano (8 km away, but note that the road is currently closed for repairs) or Buonconvento (9 km away) and then take a taxi.
Go to Asciano (see note above) or Buonconvento and take a taxi.
If you have thoughts of hiking through the Crete senese, plan carefully. The region is a semi-desert, without shade. Make sure to take plenty of water, especially in hot weather, and use a lot of sunscreen.
The Abbey of Monte Oliveto Maggiore, an active monastery which most famously includes beautiful frescoes by Luca Signorelli - Michelangelo's teacher - in the Cloister. There are also frescoes by the Sienese painter, Antonio Bazzi, called "Il Sodoma" ("The Sodomite").
There is a souvenir shop on top of the hill.
There is also a restaurant there.
Pilgrims seeking to have a spiritual retreat can stay at the Monastery Guest House  (Italian only), tel. +39 0577 70 76 52, fax: +39 0577 70 76 44, e-mail: email@example.com.; reservations can be made from 9:30-10:00 AM, 2:30-3:00 PM, and 5:30-6:00 PM.
Benedictine Olivetan nuns also offer hospitality (10 beds) to pilgrims at San Nazario, 3 kilometres from Monte Oliveto in the direction of Buonconvento, tel. +39 0577 707018.
Other tourists can stay at Agriturismo di Monte Oliveto Maggiore , Podere "Le Piazze," tel./fax: +39 0577 70 72 69, mobile phone: +39 328 7192415, e-mail: firstname.lastname@example.org.