According to some others in another thread, an Mexico visa is required outside of the "Tourist Zone".
Not that I doubt anyone, but I'll need seme clarification...
I checked online at the Consulate General of Mexico website
http://www.consulmexny.org/eng/visas_fmt_us_canada.htm
and it seems that a visa
isn't required...
This cut from their site:
United States Citizens traveling to Mexico as Tourists
Do not need a visa. However, it will be required to present one of the following documents at the airport or port of entry into Mexico:
 | Valid United States Passport; |
| Original Birth Certificate and photo official identification (i.e., driver's license); |
| Certified copy of Certificate of Naturalization and photo official identification (i.e., driver's license); |
| Voter's Registration Card with photo official identification; |
| Notarized Affidavit of Birth Facts and a official identification
|
I'm going to do more research, but anyone who definitively knows, now would be a great
time to chime in...