Alan Cressler:
0.6 LOTIS, 1.8 Meter Spacewatch, 2.3 Meter Bok Reflector, and Mayall 4 Meter Telescope, Kitt Peak National Observatory, Kitt Peak, Pima County, Arizona 1
Alan Cressler:
0.6 LOTIS, 1.8 Meter Spacewatch, 2.3 Meter Bok Reflector, and Mayall 4 Meter Telescope, Kitt Peak National Observatory, Kitt Peak, Pima County, Arizona 2
Alan Cressler:
1.3 Meter Telescope, Kitt Peak National Observatory, Kitt Peak, Pima County, Arizona 1
Alan Cressler:
Aqua Fria River, Aqua Fria National Monument, Yavapai County, Arizona 1
Alan Cressler:
Aqua Fria River, Aqua Fria National Monument, Yavapai County, Arizona 2
Alan Cressler:
Aqua Fria River, Aqua Fria National Monument, Yavapai County, Arizona 3
Alan Cressler:
Baboquivari Mountains, and Baboquivari Peak, from Buenos Aires National Wildlife Refuge, Pima County, Arizona 1
Alan Cressler:
Baboquivari Mountains, and Baboquivari Peak, from Buenos Aires National Wildlife Refuge, Pima County, Arizona 2
Alan Cressler:
Bolsa Quartzite, Middle Cambrian Age, Ramsey Canyon, Miller Peak Wilderness, Coronado National Forest, Cochise County, Arizona 1
Alan Cressler:
Bolsa Quartzite, Middle Cambrian Age, Ramsey Canyon, Miller Peak Wilderness, Coronado National Forest, Cochise County, Arizona 2
Alan Cressler:
Bommeria hispida, Santa Cruz County, Arizona 1
Alan Cressler:
Bommeria hispida, Santa Cruz County, Arizona 2
Alan Cressler:
Bryodesma arizonicum, Tanque Verde Canyon, Coronado National Forest, Pima County, Arizona 1
Alan Cressler:
Carnegiea gigantea (Crested), Sonoran Desert, Ironwood Forest National Monument, Pima County, Arizona 1
Alan Cressler:
Carnegiea gigantea (Crested), Sonoran Desert, Ironwood Forest National Monument, Pima County, Arizona 2
Alan Cressler:
Ceramic Sherd, Santa Cruz County, Arizona 1
Alan Cressler:
Ceramic Sherd, Santa Cruz County, Arizona 2
Alan Cressler:
Cliff Dwellings, Sinagua Culture, Montezuma Well, Montezuma Castle National Monument, Yavapai County, Arizona 1
Alan Cressler:
Cliff Dwellings, Sinagua Culture, Montezuma Well, Montezuma Castle National Monument, Yavapai County, Arizona 2
Alan Cressler:
Coronado Peak, Coronado National Memorial, Huachuca Mountains, Cochise County, Arizona, looking at Sierra Los Ajos, Estado de Sonora, Estados Unidos Mexicanos 1
Alan Cressler:
Gaga arizonica, Cochise County, Arizona 1
Alan Cressler:
Gaga arizonica, Cochise County, Arizona 1
Alan Cressler:
Gaga arizonica, Cochise County, Arizona 2
Alan Cressler:
Gaga arizonica, Cochise County, Arizona 2
Alan Cressler:
Glycymeris species, Hohokam Cultural Site, Pima County, Arizona 1
Alan Cressler:
Glycymeris species, Hohokam Cultural Site, Pima County, Arizona 2
Alan Cressler:
Gneissic Rocks, Middle Falls, Tanque Verde Creek, Tanque Verde Canyon, Coronado National Forest, Pima County, Arizona 1
Alan Cressler:
Granodiorite of Cocoraque Butte, Pima County, Arizona 1
Alan Cressler:
Granodiorite of Cocoraque Butte, Pima County, Arizona 2
Alan Cressler:
Hohokam Petroglyphs, John King Petroglyph Rock, on Display, Kitt Peak National Observatory, Kitt Peak, Pima County, Arizona 1
