INTRODUCTION
I was in London last Saturday for a conference at the National Autistic Society’s HQ and made use of London Underground after the conference, travelling on Northern and Metropolitan line trains. The rest of this post will largely be pictures showing this.
THE NORTHERN LINE
Catching a Northern line train at Angel means using the longest escalator in London (bear in mind that when I took the photo below I was already a few steps down):
Aboard the train at Angel I took this picture of the on-train route map of the Northern line…
Changing trains at Moorgate I got this enamel map of the relevant parts of the Northern Line…
THE METROPOLITAN
At Moorgate (and elsewhere between Liverpool Street and Great Portland Street) the Metropolitan, Circle and Hammersmith and City lines share a set of tracks, hence this enamelled route map:
The Metropolitan, Circle and Hammersmith & City lines all now have new rolling stock which is articulated rather than comprising old style carriages. The difference between the two types of stock is that the stock used on the Circle and Hammersmith & City lines has a lot of doors and comparatively little seating space owing to the fact that it is mainly used for short journeys within central London, while the Metropolitan line stock, to be suitable for longer journeys over less densely used track has much more seating and fewer doors.

Here is the internal route map from this same train: