How does mentioning sleeping on the Northern line and waking up at Morden indicate being from London?

If you've ever ridden the Northern line of the London Underground, you've probably heard the phrase 'I fell asleep on the Northern line and woke up at Morden' before. This seemingly random statement is actually a bit of a cultural phenomenon and a way for Londoners to identify one another.

The Northern line is one of the busiest and most popular lines on the London Underground, and Morden is the southernmost station on the line. So, if someone claims to have fallen asleep on the Northern line and woken up at Morden, it means they've been on the train for a while and have gone through the majority of the stops. It's a bit of a joke because Morden is so far south that it's almost out of London, so falling asleep and waking up there is almost like waking up in a different town entirely.

But why is this phrase such a cultural touchstone? For Londoners, it's a way of bonding over shared experiences. Almost everyone who has lived in London for any length of time has fallen asleep on public transportation at least once, and the Northern line is notorious for being a bumpy ride. So, when someone mentions falling asleep on the Northern line and waking up at Morden, it's an instant connection. It's also a bit of a badge of honor – surviving a long journey on the Northern line is something that only true Londoners can do.