This downloadable PDF set includes 3-part cards for 16 natural wonders of North America: Arenal Volcano, Basaltic Prisms of Santa Maria Regla, Denali, Grand Canyon, Grand Prismatic Spring, Great Blue Hole, Hamilton Pool Preserve, Mendenhall Glacier, Monument Valley, Niagara Falls, Perce Rock, Semuc Champey, Banff National Park, Sac Actun, Half Dome, Horseshoe Bend. The 8-page PDF file contains: 16 control cards, 16 picture cards, 16 name labels Control card measures 8 cm x 11 cm