Lyd is a narrow gauge steam locomotive built by the Ffestiniog Railway in their own Boston Lodge shops over a period of 15 years.

[3] Although externally similar in appearance, to Lew, Lyd incorporates a number of modern design and construction techniques to improve overall efficiency.

In order to navigate Garnedd tunnel, Lyd's cab is fitted with removable side panels to change the roof profile.

Lyd was painted in early 1950s British Railways lined black livery and carrying the number 30190.

Initially completed as an oil-burner, but designed for easy conversion, Lyd was converted to coal-burning during the autumn of 2011, and was first fired with coal on 12 December.