I'm interested in a 10 day visit to Central America. We are 4 adults (parents and 2 adult children). We like to hike and meet locals. At least one of us is fluent in Spanish but we'd rather trek with a local than self-drive. we are presently set on Guatemala and/or Costa Rica. Any ideas would be helpful.
Depending on your experience and desires in terms of costs, the answers may vary. If you've never been to Central America, Costa Rica and Belize will be much easier to manage than Guatemala. If cost is a concern, Guatemala is less expensive, but also less developed in terms of tourism.
In Guatemala, Antigua offers some fun volcano hikes, and it is one of the most beautiful cities of its size around. It is not too far to Lago de Atitlan from there. Tikal is a must see, and there are some hiking trips in that area now. Monumento Natural Semuc Champey is a trek but well worth it.
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I spent a couple of days on the Pacific coast in Monterrico a few years ago and it was a lovely place. Small community not crowded with tourists, great opportunity to see sea turtles laying eggs or release of young turtles to the ocean from protected hatcheries on the coast. This depends on the season. Apart from that there is Monterrico Mangrove Natural Reserve where you can go on a guided early morning boat tour.
Coast is very scenic and beautiful as well, but ocean not that much for swimming.