Mayan Blue - Sistema Naranjal
Located just south of Tulum, Mayan Blue is one of the two main entrances to Sistema Naranjal. The other main entrance, Naharon, is just across the road. Naharon is very dark due to all surfaces being stained by tannic acid that flows from a swamp further upstream. Mayan Blue has both dark and light colored walls in fresh and salt water zones and likely received its name due to iridicent blue color of the water inside the white sections of the cave. Or at least it appears to be blue in the reflections of HID lights. The cave has several entrances and half a dozen different lines from Mayan Blue cenote, so there is lots to see, however, buddy and I avoided this site in the past for safety concerns - there had been a few incidents at this site. The concerns were still valid as of fall 2007, so check before you go.