London Underground at +420 V, giving a potential difference of 630 V. On the sections of line shared with mainline trains, such as the District line from East Putney to Wimbledon and Gunnersbury to Richmond, and the Bakerloo line north of Queen's Park, the centre rail is bonded to the running rails. The average speed on the Underground is 20.5 mph. Outside the tunnels of central London, many lines' trains tend to travel at over 40 mph in the suburban and countryside areas. The Metropolitan line can reach speeds of 62 mph. The London Underground was used by 1.379 billion passengers in
Line 1 (Ningbo Rail Transit) District. Then it passes Ningbo East New Town and then go overground. Finally the metro line extends into Beilun District and ends there. The section between Gaoqiao and Ningbo East New Town has been constructed as the first phase which started service on May 30, 2014. The rest section from Ningbo East New Town to Beilun District opens on March 19, 2016. The line has 28 stations in total, of which 12 are elevated and the rest are underground. Till June 2014, 20 stations of Line 1 are operational. Line 1 (Ningbo Rail Transit) Line 1 of Ningbo Rail Transit