Wait wait wait. Actun Tunijil is located in the Tapir Mtn Forest Reserve around Teakettle village off the Western Hywy. Caves Branch is in another area, outside of Belmopan.
Xibalba (spelt wrong I'm sure) is the maya word for underworld, which was reached thru caves and the roots of the Ceiba tree. The people at Caves Branch have a cave trip that is so named.
7 yr old for Actun? I don't know, depends on what your 7 yr old is like. I took an 8 yr old, but this kid has been in plenty of caves, climbed plenty of rocks, etc. Not sure this is for kids. They'll get cold and they'll be spending alot of time wet and uncomfortable doing something that is fascinating to you, but maybe not for them. I'd say your best bet for a cave trip with kids that age would be Barton Creek Cave off the Mtn Pine Ridge road.
The people at Caves Branch will not prebook a kid under 11 until they have met and seen the kid. So before you book with them, find out what the deal is for kids.
My choice for guides at Actun? Emilio Awe, hands down, without a doubt.
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