Related by context. Frequent words. (Click for all words.) 66 Chaco Canyon 64 cliff dwellings 58 Anasazi 57 Olmecs 57 cypress swamp 56 Petroglyphs 55 adobes 55 limestone cave 54 Inca Empire 54 kiva 53 Chihuahuan Desert 53 Ioway 53 lava tubes 53 Hohokam 52 Palenque 52 burial mounds 51 limestone caves 51 earthen mounds 51 Palaeolithic 51 Mesoamerican 51 petroglyphs 51 cenotes 51 Kumeyaay 51 creek bottoms 51 Mimbres 51 Bighorn Basin 51 Durrington Walls 51 adobe brick 51 Puebloan 50 Algonquian 50 petroglyph 50 Superstition Mountains 50 Cahokia Mounds 50 prehistoric 50 pictographs 50 mesa 50 Sandia Mountains 50 Sierra Madre Mountains 49 upland habitat 49 buffalo herds 49 ancient 49 middens 49 Aztec empire 49 Mesoamerica 49 Canyon de Chelly 49 Hebgen Lake 49 coquina 49 Omo River 49 Tenochtitlan 49 lava tube 49 archeological digs 49 Gila Wilderness 49 ancient Mayan 49 Painted Desert 48 pueblo 48 butte 48 tule 48 archeological 48 limestone formations 48 presidio 48 archeological sites 48 Lassen Peak 48 archaeological sites 48 Redfish Lake 48 temperate rainforest 48 Harappan 48 Mayan civilization 48 alfalfa fields 48 extinct volcanoes 48 Santa Rosalia 48 pre Columbian 48 rock outcrops 48 Yucatán 48 archaeological ruins 48 ancient Babylon 48 Tiwanaku 47 pueblos 47 Egyptian pyramids 47 pre Incan 47 archeologists 47 conifer forests 47 Sierra Madre mountains 47 Miwok 47 Spanish conquerors 47 Mayan 47 landform 47 Harappa 47 Taos Pueblo 47 Native Americans 47 Huichol 47 radiocarbon dates 47 wigwams 47 Sangre de Cristo Mountains 47 Incas 47 Tikal 47 Book Cliffs 47 cypress swamps 47 Snoqualmie Falls 47 Excavated 47 paleontological 47 heiau