Adam summed it up well, just wanted to add a note on where we went today, to Kartchner Caverns State Park. It's an amazing cavern in the mountains of southeastern AZ near Benson/Ft Huachuca.

No photography is permitted so you will have to check the link:

http://azstateparks.com/Parks/KACA/index.html

I absolutely recommend a visit and funnily enough there was a couple from Wooton Basset (near London) on our tour....those English get everywhere!

XX Andrea