HVDC Ekibastuz–Centre is an unfinished HVDC transmission line between Ekibastuz in Kazhakstan and Tambov (Centre substation) in Russia whose construction was started in 1978. It was planned to have a length of 2,414 kilometres (1,500 mi), which would have made it the longest powerline of the world with a maximum transmission rate of 6,000 MW and a transmission voltage of 750 kV between conductor and ground (respectively 1,500 kV between conductors). For this line the erection of 4,000 pylons, most 41 metres (135 ft) tall, were required.