http://www.greengauge21.net/assets/GG21_HS2.pdf Green Gauge 21 - High Speed Two] The proposed route of HS2 into London will bring the line very close to the existing High Speed 1 (HS1) line which terminates at St Pancras station; at their closest points, the two high-speed lines will be only 0.4 miles apart, and the Department for Transport (DfT) examined various proposals for connecting HS1 and HS2.