Kohunlich definitely lived up to its billing as a noteworthy archeological site in moist, tall forest. No building in particular stood out, but there was a nice variety of large and small buildings, including residential areas, a ball-court, the main structure with the featured masks, and some good birding and moss-covered palm trunks. as others have noted, it was very uncrowded, although some workers were tidying up a few overgrown shrubs to keep the area open. there was a nice view from the "27 steps" residential area, but not the cliff mentioned in some guide-books. birding was excellent, but (as usual) make sure you bring plenty of water if you visit in the hot season, since you will sweat a lot in the high humidity. This site can be reached in about an hour's drive from Chetumal, and probably a bit less from Bacalar, another spot with lodging. we visited nearby Dzibanche and Kinichna on a different morning, but you could easily do all sites in one day.
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