Disclaimer: I do not own Harry Potter, Albus Dumbledore or the London Underground. Any text in bold was taken straight from J. K. Rowling. I know it seems lazy, but it's a perfect description!

Summary: Albus Dumbledore meets an interesting young child on the London Underground. Inspired by the Harry Potter and the Half Blood Prince film, and in particular the line "I like riding around on trains. It takes my mind off things."

"The next station is Shadwell. Change here for the DLR."

A young boy squeezed down the middle aisle of the train, past commuters with their heads buried in papers, past tourists looking at the line maps, puzzled, to the end of the carriage. Any other city, perhaps, he would be challenged - "Where's your mum?" - but he'd been wandering around London for two years already, and nobody had said anything.

This boy was Harry Potter.

It had all started when Uncle Vernon and Aunt Petunia had taken Dudley to the London Dungeon, and there was nobody to take him for the day (Mrs. Figg had gone on holiday). It had happened very quickly - Dudley had tripped him up as they left the train at London Bridge, and before he could get up, the Guard had blown his whistle, and the train was on its way to Borough. How he remembered that day.

Not that he regretted it.

He'd spent several hours in Morden that day, poring over a tube map he'd managed to find, before heading to Waterloo to try and catch the Dursleys on their way back to Surrey - but they just walked straight past him. He'd picked up a pie from a kind street seller on the Southbank, and headed back into Waterloo, getting back onto the tube again.

Two years later, he knew a lot more. The Tube closed at midnight, but he could usually have a nap in one of the more complicated stations (like Tottenham Court Road), so long as he stayed away from the escalators.

He'd hated escalators ever since that day. It had been barely a month since he'd first lost the Dursleys. He'd been in King's Cross, changing to his next train, when he saw that the escalator ahead of him had caught fire.

He still remembered the screams.

Snapping back to reality, he noticed something very strange. Or rather, someone. It was extremely strange for there to be an empty seat on the tube, especially during rush hour. Even if this was the East London Line - but that was nothing to the man on the seat next to it.

He was tall, thin and very old, judging by the silver of his hair and beard, which were both long enough to tuck into his belt. He was wearing long robes, a bright yellow cloak which draped across the seat and high-heeled, buckled boots. His blue eyes were light, bright and sparkling behind half-moon spectacles and his nose was very long and crooked, as though it had been broken at least twice.

Harry made his way next to the man, and sat down. The man turned his head to look at him, and for a second, Harry thought he saw recognition in the man's eyes, but that faded almost immediately, and the man's eyes strayed back down towards his knee. Harry looked down as well, and gasped. The man looked up at him.

"Sir, your knee - it's got a tube map!" Harry blurted out.

"Aah, yes. It's a quite remarkable scar, isn't it? I acquired it in a fight back in 1980," said the man. Harry stared at him, trying to imagine him fighting. After a moment, he gave up, but he suddenly noticed something that looked off.

"Sir, what's happened to the Aldwych line?" he asked, perplexed. And indeed, the little stub poking out from Holborn was absent.

"That is a curious little tale, my boy. You see, my scar does not change over the years - indeed, when I first procured it, I was mystified as to the lack of stations in the top left. However, when the Watford Junction services disappeared, I understood - and further confirmation came with the Heathrow loop."

"But what does it mean?"

"I believe that when the network on my knee matches the current map, then it is time."

"Time for what?"

"It will be my time to die." Harry gaped at the man.

"But sir..."

"To one as young as you, I'm sure it seems incredible, but after all, to the well-organized mind, death is but the next great adventure." Harry looked confused, and the old man chuckled.

"The next station is Whitechapel. Change here for the District and Metropolitan Lines. Alight here for the Royal London Hospital."

"This is my stop," said Harry, and the old man nodded at him. Harry made his way off the train, and watched as the doors closed behind him, and the train clanked away. Harry stood on the platform for a few seconds longer than usual, then turned away towards the subsurface lines. Hopefully, the pasties would still be hot in the shop in Barking.

Albus Dumbledore looked out as the train started to move. The boy was still standing on the platform, and as the air currents from the slipstream started up, the hair on the boy's forehead moved aside for a second. He began to shout out in recognition, but the train was already pulling around the corner.

A/N: What do you think? The review box at the bottom is your friend. Also, if you'd like more from this universe (Hagrid and the letter, the Chamber of Secrets King's Cross debacle or perhaps just some more tales of Harry's early years), please write a message!

As to Dumbledore being able to look at his knees, he was wearing robes at the time, and uncovered his knee so he could read the map. He's a hipster going to Shoreditch, what do you expect?

If you think the tube as described is inaccurate, I can attempt to give my reasoning - London is as accurate to 1989 standards (when this story is set) as I can make it, not being born until the mid nineties. The only inaccuracy is the announcements. The A Stock is the type of train running on the ELL at the time, and the Scarred Man - well, that's up to you.