El Mirador was one of the earliest known Maya cities, dating from B.C. 150 - A.D. 150 (Millard 44). It was discovered in 1930 as a result of an aerial survey of the Maya Lowlands. Ian Graham was the first archaeologist to explore the city in the 1960's. It was difficult to reach, as there were no roads or airstrips and by foot it took from 2 to 4 days to reach.
The limestone buildings at the site were subject to years of erosion due to monsoon rains (Hellmuth 97). Graham studied sherds and sculpture fragments dating from the Pre-Classic Period.
El Mirador is located in the lowland core where some of the most fascinating archaeological finds have been discovered. By the late Pre-Classic Period, a hierarchy of sites had developed. El Mirador was situated at the center of a series of causeways which lead to other cities, the most notable being Nakbe. It's central core was 2 km from east to west, similar to Tikal. Built in this area were a number of immense complexes, the most distinctive being the Triadic Pyramid. El Tigre is today the largest explored pyramid, having a surface area six times that of Temple IV in Tikal. Excavations and testing indicate that most of the construction took place in the Late Pre-Classic Period (Danien 133).
Based on size alone, it's easy to conclude that a very powerful elite group lived here at one time. Their technology allowed them to harness both human and natural resources in a most proficient way (Danien 134).
Danien, Elin C. and Robert J. Sharer. New Theories on the Pyramids, Kingfisher New York 1996.