0-12-0

Other equivalent classifications are: The first example of the 0-12-0 was the Pennsylvania, designed by Jame Milholland for the Philadelphia and Reading Railroad and built at its own shops in 1863.

It weighed fifty tons and was, at the time, the heaviest steam locomotive in the world.

[1] It was intended as a pusher engine for Pennsylvania coal trains on the Falls Grades near Philadelphia.

The only others of the type, was a class of ten 0-12-0T locomotives built by Hanomag in 1922 for the Bulgarian State Railways (BDŽ).

[3] They were built as two-cylinder compound locomotives, with a 15-kilogram-per-square-centimetre (1.47 MPa; 213 psi) boiler feeding a 620-by-700-millimetre (24.41 in × 27.56 in) high-pressure cylinder discharging to a 900-by-700-millimetre (35.43 in × 27.56 in), both of which were connected to the 1,340-millimetre (52.76 in) driving wheels.