This map categorizes transmission line networks across the United States by voltage levels ranging from 3 kV to 1,00 kV. The dense web of lines highlights key corridors and regions with heavy transmission infrastructure, particularly in the eastern U.S. while sparser coverage is visible in parts of the West and Alaska. The black boundary lines mark the major interconnects –Western, Eastern, and ERCOT—providing a visual reference of how the grid is divided and managed.