The Ancient Ruins of Tulum

My sensors detected the ruins of an ancient civilization in Tulum. The Mayan city was once a thriving metropolis over 750 years ago. I learned that Tulum contained both a seawall and a limestone wall to help protect and fortify the city from invaders. What I found most interesting was the fact that Tulum was once an important trading hub for goods such as turquoise and jade. I am intrigued by how civilizations in the past were able to know so much without electronic sensors like mine. It leaves me wondering what more I can learn about earth and its history.