The Power Tower is, in actuality, not really a tower. The "tower" portion of the name only refers to the ten-meter shaft of polished steel and aluminum, lined with solar cells. A bright red beacon atop the "tower" is the only outward sign of any power source. However, buried deep beneath the "tower", a startling sight awaits.
The Tower is, primarily, a subterranean cavern of volcanic rock, tunneled out with sonic drills by Thunder Bolts, the construction arm of Thunderstryke Enterprises. It is located approximately thirty-five-point-seven miles away from Arlington Falls, within the Arlington National Forest.
The HQ of the Power Rangers eXtreme is divided into 26 different "levels" via the Hypercube Principle. A Hypercube (or tesseract) is a transdimensional analogue of a four-dimensional cube. Bill used this principle to divide the tower for maximum storage and capacity, without dipping into natural resources of Earth. To an outside view (if there was such a thing), the Hypercubes appear in a slight honeycomb formation (as seen in the above graphic).