Just down the road from Gavillaccio is the Roman Pieve of San Romolo at Gaville, which is well worth a visit. Some other Roman churches in the area can be visited at Gropina, Reggello and Cascia and if you venture into the hills around Siena and Casentino there are plenty more.
From 1 April to 30 June and from 1 September to 30 October
Sundays from 15:00 - 18:00
And on other days by appointment:
Tel. +39 0559501071