Source: WTL© digital photograph (2009) taken on site at the Templo Mayor, Mexico City.
Comments: We are now beginning the tour of the archeological site. (The photographer at the raining above at current-day ground level and I were taking photos of each other. She was possibly interested in my Mexican hat.) Notice how much higher modern ground level is than, roughly speaking, ground level was when the Templo Mayor was a functional sacred site. When the Spanish conquistadors destroyed the Aztec capital, they tore down pyramids, palaces, and buildings and created a higher ground level. Some excavations of this site began in the first years of the 20th century, but serious urban renewal spurred totally serious and scientific excavation.
Humanities Issue: Keeping in mind the brutal nature of the war of defense/conquest and the fact that Tenochtitlán / Mexico City was and is built in the middle of a lake and swamp, reflect on the fact of the double ground level.