The ground return electrode for the 850-mile Pacific Intertie DC line consists of 24 silicon-iron alloy poles, anchored in cement and planted into the ocean floor, one mile off of Will Rogers State Beach. The array is connected by a pair of buried wires to the shore (accessed through vaults next to the parking lot at Gladstones Restaurant on Pacific Coast Highway), and eventually to the Sylmar Converter Station, the official terminus of the 500,000 volt DC transmission line. Long distance DC lines require these ground return electrodes at either end, to carry the current through the ground in the event of some system anomaly.