This is from the map men's video about British cities, a (half satirical) list of the "8,007 more important things [the UK government has] to worry about". I gave it a quick search, but the only thing I got was some railway line in Australia.
Any help is appreciated!
My guess would be that it's referring to the recently-opened Elizabeth Line, a railway line in London. Possibly referring to something they've mentioned in a previous video.