Kibo

If you can get the wife to bend the US rule, Orizaba in Mexico is a good objective. Gets you to 18,500 so you can experience the joys of AMS, appetite loss, cold, etc. :-) All the other advice about fitness and enduring make total sense. Also, check out www.mtnathlete.com and http://www.mensjournal.com/magazine/everything-you-know-about-fitness-is-a-lie-20120504 As a flatlander you'll have unique challenges getting in shape, and this type of training can go a long way. You can skip Adams, Baker and Shasta and go right to Denali prep and they'll get you ready to go.