1. From the Rhymney Railway's opening in 1858 it had a junction with the Taff Vale Railway at Walnut Tree from which it had running powers to Cardiff. It was not until 1871 that it had its own direct route to Cardiff via Caerphilly tunnel. The original small engine shed survives near to present day Taffs Well station (the Taff Vale Railway's former Walnut Tree station).
(A Guide to the Industrial Archaeology of South East Wales, AIA, 2003)
B.A.Malaws, RCAHMW, 21 September 2005.

2. Demolition of the Walnut Tree Engine Shed began in early 2019 as part of the £100m development of the South Wales Metro depot at Taff's Well.

(Sources: Information from a member of the public; `South Wales Metro: New £100m train depot for Taff's Well?, BBC news, 11.06.2018; Anthony Lewis, `£100m South Wales Metro depot for Taffs Well approved by planners, Wales Online, 06.07.2018; Rhondda Cynon Taf Planning and Development Committee Report of the Service Director, Planning, Application 180314, 05.07.2018)
A.N. Coward, RCAHMW, 14.03.2019