Only the 2% of the Mayan ruins in Palenque has been discovered. It means that more than a thousand of building are still there, underneath the ground covered by rich vegetation. By walking into the jungle you can suddenly spot part of ancient buildings. The 98% of the area is covered by a dense vegetation. While walking into the jungle you can imagine to find a door that nobody has seen before. An entrance that leads you to the tomb of a great Mayan emperor, covered by gemstone and gold.
By the way, the archeological site of Palenque is just stunning, way more than we could possibly imagine.