In Solu-Khumbu, villages can range from just three or four households to more than a hundred houses in the large towns of Khumjung and Namche Bazaar. In higher valleys, where arable land is scarcer and fields are smaller, individual houses sit in the midst of their adjoining fields, which are separated by stone walls. In the lower, more fertile valleys, houses are usually clustered in central locations surrounded by the fields of the various village residents. Many villages may include a community temple, as well as a communal mill and the Religious monuments called chorten (Tibetan mchod rten, Nepali stupa ), a distinctively shaped reliquary mound. There are a few government schools in the region. Sherpa houses are substantial buildings of stone covered with plaster, worked with wood in the interior and with wooden shingles on the roof. Houses have at least two stories, the lower story usually serving as an animal shed and storage area. The main living quarters on the second story are built around a hearth area; there are shelves on the walls for the storage of kitchen and Household items, as well as the family's collection of large copper kettles, heirlooms that serve as exchange and display items. There is no furniture, but the interior walls are lined with built-in platforms and benches for eating, sleeping, and entertaining guests.