Outline map of the proposed HS4Air railway line, which would connect High Speed 1 to High Speed 2 via Heathrow and Gatwick Airports. The line was proposed in 2018 and is currently not confirmed or funded.
<a href="//commons.wikimedia.org/wiki/User:Cnbrb" title="User:Cnbrb">Cnbrb</a>
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<span class="int-own-work" lang="en">Own work</span>