upper falls of grand canyon of the yellowston

upper falls grand canyon yellowston country nps national park service river seasons nature elements water yellowstone america american basin caldera colorful creeks dormant ecosystem first flow forest forests geothermal vents getaway geyser grassland hot lakes meadows places recreation recreational rivers scenery scenic smoke state states streams thermal trails travel trip united usa vacation vent volcanic volcano warm waterfall waterfalls western wildlife wy wyoming south rim drive views