It&#x27;s &quot;normal&quot; railway. Big trains, which continue onto the national railway network after leaving the tunnel.<p>Visitors to London especially don&#x27;t need to care about this, and the name tells then to treat it like the other underground lines: there will be trains every two minutes, and a special ticket isn&#x27;t required.<p>Also,  Crossrail 2 is being planned.