Ivor is the familiar name of the locomotive of the Merioneth and Llantisilly Rail Traction Company Limited. This name was regarded as being a long name for a little engine so his friends just called him Ivor.

Ivor resides in a shed at the end of the railway line.

Unlike most steam locomotives, Ivor has a mind of his own. He can drive himself and, using his whistle, can speak. His fondest dream was to sing with the Grumbley and District Choral Society, a dream that was realised when his whistle was replaced with three pipes from an old calliope. He became first bass of the choir, as well as providing them with a means of getting from place to place.

Ivor enjoys doing all sorts of things that people do. As well as singing in the choir, he likes visiting the seaside, making tea from his boiler and spending time with his friends. He is fond of animals, and has several of them among his friends. He can be wilful and disobedient at times, and it is not unknown for him to go and do his own thing when he should be working. He dislikes shunting and timetables.

Ivor's work takes him to Llaniog, Tan-y-Gwlch, Llanmad, and Tewyn Beach. He was also regularly taken to Grumbly Town and Grumbly Gasworks.