Trekking in the western side of the Sienese Montagnola in search of several quarries of white, grey and yellow marble, locally called "broccatello". In the various quarries we will observe traces of mining techniques and interesting geological issues. Furthermore, caves of some speleological values and climbing walls, give new life to this deep cuts. During the day, the occasion will be an opportunity to discover some interesting geological, geographical, historical and social aspects of this part of the territory. The more intrepid hikers can explore a small cave.