Crissy Field, a former U.S. Army airfield, is now part of the Golden Gate National Recreation Area in San Francisco, California, United States. Historically part of the Presidio of San Francisco, Crissy Field closed as an airfield after 1974. Under Army control, the site was affected by dumping of hazardous materials. The National Park Service took control of the area in 1994 and cleaned it up, and in 2001 the Crissy Field Center opened to the public.
Australian Rainbow Photograph by Randy Olson - National Geographic A double rainbow frames termite mounds in Australia's grasslands. Double arcs happen when light is reflected more than once in an atmospheric water droplet.