Editing High Speed 1 (section)

=== Tunnels ===
After local protests,<ref>{{cite web |url=https://news.google.com/newspapers?id=L9ANAAAAIBAJ&pg=6778,3597181&dq=channel+tunnel+rail+line+protests&hl=en |title=Britons protest tunnel rail routes |work=[[Tampa Bay Times|St Petersburg Times]] |date=27 February 1989 }}{{Dead link|date=April 2022 |bot=InternetArchiveBot |fix-attempted=yes }}</ref><ref>{{cite news |url= https://money.cnn.com/magazines/fortune/fortune_archive/1989/11/20/72772/index.htm |title= Full Throttle towards a new era |quote= To put some steel into 1992, the Europeans are building a network of tunnels, bridges, and high speed railways |publisher= CNN |first= Shawn |last= Tully |date= 20 November 1989 |access-date= 3 August 2020 |archive-date= 23 November 2020 |archive-url= https://web.archive.org/web/20201123200026/https://money.cnn.com/magazines/fortune/fortune_archive/1989/11/20/72772/index.htm |url-status= live }}</ref> early plans were modified to put more of the route into tunnels up until a point approximately {{convert|2|km|mi}} from St Pancras. Previously the CTRL was planned to run on an elevated section alongside the [[North London Line]] on approach into the line's terminus. The twin tunnels bored under London were driven from [[Stratford, London|Stratford]] westwards towards St Pancras, eastwards towards [[Dagenham]] and from Dagenham westwards to connect with the tunnel from Stratford. The [[tunnel boring machine]]s were {{convert|120|m|ft|0}} long and weighed {{Convert|1100|t|4=0}}. The depth of the tunnels varies from {{convert|24|to|50|m|ft}}. The two London tunnels are {{Convert|7.5|km|mi}} and {{convert|10.1|km|mi}} in length, split by [[Stratford International station]].<ref name=":4">{{Cite web |date=May 2013 |title=HS1 Sectional Appendix |url=https://highspeed1.co.uk/media/3txaz5b5/sectional-appendix-to-the-hs1-rule-book-ref-c-02-os-05-2002.pdf |access-date=17 November 2021 |website=High Speed 1 |page=A10 |quote=LONDON TUNNEL 1 (7538m)}}</ref><ref name=":5">{{Cite web |date=May 2013 |title=HS1 Sectional Appendix |url=https://highspeed1.co.uk/media/3txaz5b5/sectional-appendix-to-the-hs1-rule-book-ref-c-02-os-05-2002.pdf |access-date=17 November 2021 |website=High Speed 1 |page=A12 |quote=LONDON TUNNEL 2 (10120m)}}</ref>

Other major tunnels along the route include a {{convert|3.1|km|mi|2|abbr=in|adj=on}} tunnel underneath the River Thames at [[Thurrock]] in Essex<ref name=":3">{{Cite web |date=May 2013 |title=HS1 Sectional Appendix |url=https://highspeed1.co.uk/media/3txaz5b5/sectional-appendix-to-the-hs1-rule-book-ref-c-02-os-05-2002.pdf |access-date=17 November 2021 |website=High Speed 1 |pages=A14 |quote=THAMES TUNNEL (3115m)}}</ref> and the {{convert|3.2|km|mi|2|abbr=in|adj=on}} [[North Downs Tunnel]] near [[Maidstone]] in Kent.<ref name=":1">{{Cite web |date=May 2013 |title=HS1 Sectional Appendix |url=https://highspeed1.co.uk/media/3txaz5b5/sectional-appendix-to-the-hs1-rule-book-ref-c-02-os-05-2002.pdf |access-date=6 January 2023 |website=High Speed 1 |page=A19 |quote=NORTH DOWNS TUNNEL (3199m)}}</ref>