Lehman Caves

http://www.nps.gov/grba/cavephotos.htm
http://www.earthscope-eon.org/dynamicimages/htmlpages/200.html

Castillo de san Marcos

http://www.nps.gov/casa/
http://members.cox.net/johnahamill/castillo.html

Buck Island Reef

http://www.ecani.com/buck.island/
http://usparks.about.com/library/miniplanner/blbuckislandnm.htm

Effigy Mounds

http://www.nps.gov/efmo/
http://effigymounds.areaparks.com/