My friend Joan and I were staying at Ni'tun Private Reserve on Lake Petén Itzá near Flores, and planned to visit several Maya sites in the Petén region, but were most excited about visiting Aguateca. What an adventure it was! Our guide Bernie of Monkey Eco Tours drove us to the town of Sayaxché on Río de la Pasión, where we embarked on a 90-minute boat ride on a gloriously sunny day. About halfway there, the river opened into Petexbatún Lagoon, a protected wildlife refuge where we spotted a variety of birds including cormorants, herons, osprey and vultures. When the boat docked at Aguateca, we had an uphill hike and soon were within viewing distance of the site's most extraordinary feature - La Grieta (translation: fissure or rift). At Aguateca it signifies the geological chasm that divides the site and provided its occupants with a natural defensive wall. As we craned our necks to look up, it was easy to imagine being pelted by rocks or other weapons from above. As we continued toward the ruins, our hike took us through a narrow portion of the chasm. The sun's rays combined with fog from the humidity to create somewhat ethereal lighting when I took this photo of Joan. Although you won't find imposing temples like Tikal’s here, the ruins at Aguateca are significant, and among the best preserved of the Mayan sites in Guatemala. Because of the travel time, you'll need a full day to visit and if Bernie is your guide, you'll be an expert in Mayan culture by the end of the day.