Most Mesa Verde cliff dwellings were built between 1180 and 1300 CE. Paths linked homes with fields, storage places, water sources and public buildings, so these alcoves were part of a connected community rather than isolated houses. Many cliff dwellings sit near seep springs. Extended drought may have made mesa-top reservoirs less dependable, and easier access to water is one likely reason people moved homes into the alcoves; the reasons for the later migration south are still not fully understood.