GWR 3600 Class
The Great Western Railway 3600 Class was a class of 2-4-2T side tank steam locomotive, designed by William Dean and built at Swindon in three lots in 1900-1903:
History
Dean had built an experimental 2-4-2T numbered 11, whose success led to the cancellation of another batch of 2-4-0 "Metro" Tanks and the construction of the 3600s in their place. The new 2-4-2Ts had coupled wheels and cylinders. The second batch were slightly longer than the prototype, resulting in greater tank capacity, and the third lot, delivered under Churchward, were slightly larger again, and had taper boilers. The class gained the nickname "Birdcage" due to their unusually spacious cabs.| Year | Quantity | Lot No. | Serial Nos. | Locomotive numbers | Notes |
| 1900 | 1 | 130 | 1907 | 11 | renumbered 3600 in 1912 |
| 1902 | 20 | 134 | 1866–1885 | 3601–3620 | Serial numbers out of sequence |
| 1903 | 10 | 143 | 2013–2022 | 3621–3630 |