canyon, old faithful, cataract canyon, aqueduct, donner pass, dam, pyramids, freeway, flume, carlsbad caverns, wasatch range, teton range, great pyramid, arroyos, sangre de cristo mountains, mohave, mohave desert, petrified forest, aerial tramway, hydroelectric, cheops, bighorn river, barney oldfield, alexandre gustave eiffel, organ pipe, buttes, grand coulee, gondola, waterfalls, harney peak, sonoran desert, platte river, horseshoe falls, trestle bridge, parkway, tacoma narrows bridge, painted desert, cableway, yangtze, john augustus roebling, headrace, hydropower, truss bridge, machu picchu, tappan zee bridge, coulee, mesa, mackinac bridge, stagecoaches, nikola tesla, tsangpo, waterwheel, erie canal, mount ranier, mojave desert, comstock lode, dust bowl, bridge, suspension bridge, panoche, hualapai, spillway, desert, anasazi, iguazu falls, penstock, canyonlands, atomic age, stagecoach, superhighway, hydroelectric turbine, chairlift, snowshed, iguassu falls, interstates, aswan dam, tyrannosaurus rex, pamirs, drawbridge, spaceship, highway, zambezi river, lassen peak, paiutes, tunnels, funicular railway, great smoky mountains, observation tower, rapids, kaieteur falls, ropeway, rockslide, mountaintop, cavern, reservior, skyscrapers, vannevar bush, reservoir, pecos river, mesa verde national park, cog railway, sinai desert

battle born state, nevada, sagebrush state, silver state

dam, dike, levee