june 26, 2018 lakehead / ca / usa - beautifully d formations in shasta lake caverns national national landmark, northern

amazing america ancient attraction beautiful ca calcite california cave cavern caves caving chamber colorful column dark decorated deep earth editorial use only formation formations geological geology hole inside interior karst light limestone mineral mountain national natural nature old rock speleology stalactite stalagmite stone subterranean tourism travel tunnel underground united states usa water wet