Pound for pound, Guatemala packs some of the most excitement of any country in the Western Hemisphere. You can explore Mayan ruins (including the world-famous Tikal), walk the history-drenched streets of Antigua, sail Lake Atitlan, relax on the beach, hike a volcano, or experience big city life.
Guatemala City has a bad reputation for violence, although this can be avoided quite easily. Many areas once considered lost to shootings and kidnappings are being cleaned up and revamped quite well. Be sure to check out Zones 4, 10, and 1 (just be sure to go during the day).