How big is a 1,500-mile square in familiar geography?
It spans from New York City to Denver, then Denver to Mexico City, then from Mexico City out into the South Atlantic and back to New York. That forms a 1,500-mile square, and the city also rises 1,500 miles high.
Les explains that the city is foursquare and measured as a cube: 1,500 miles long, 1,500 miles wide, and 1,500 miles high. To make that size understandable, he compares it to traveling from New York City to Denver, then Denver to Mexico City, then Mexico City out into the South Atlantic and back to New York—a 1,500-mile square. He also notes it rises 1,500 miles upward. He says some think it could be a pyramid, but he doubts that and prefers a cube.