Over the Christmas break while visiting my family "oop north" we visited the Manchester Museum of Science and Industry. I remember visiting as a child and found it really exciting, and in that respect it hasn't changed; there's a floor full of hands-on "experiments" for kids to play with that demonstrate scientific principles, a hall full of aircraft, a (replica) sewer, and a "Power hall" full of stationary and rail steam engines.
In this hall is a 3' gauge Beyer Peacock "Pender" from the Isle of Mann that has been sectioned to show how a steam engine works, it's a great educational visual aid and even to someone who knows the principle, the detail of the fittings is interesting. It does seem a sad waste of a lovely engine, though fortunately the other side looks unmolested.
Pender is the smallest but there are a few other Manchester-built locos including one from India, and an electric that ran in Holland, but the biggest loco is also Narrow Gauge - this 3'6" gauge Garrat that ran in South Africa.
Outside, this unassuming brick building is the original Manchester station, dating from the opening of the first public railway in 1830.
While short passenger rides through the site were provided by this well-kept industrial loco.