Hello,
It you're looking to be a archaeo-tourist and Guatelmala are great places to look. The are several American Universities that have sponsored digs in
country (neither Belize or Guatelmala has the cash to do it themselves). Last time I was there the University of Minnesota and the University of
Wisconsin both had digs going.
There a MANY unexplored sites. most are mounds covered with plant growth for the jungle reclaims it's territory quickly in that part of the world.
The farther you get from "civilization" the more dangerous it gets, so if you intend to strike off for yourself be prepared for the worst.
If you just want to be a tourist go to TIKAL. It is amazing. Just don't lie down on the sacrifical altar during the Summer Soltice.
hrxll