| Ceylon Government Railways Class C1 and C1a | |
| Powertype: | Steam |
| Builder: | Beyer, Peacock & Company |
| Serialnumber: | C1, 6410 C1a, 7160-7167 |
| Builddate: | C1, 1928 C1a, 1946 |
| Whytetype: | 2-6-2+2-6-2 |
| Cylindercount: | Four, outside |
| Cylindersize: | 16x |
| Valvegear: | Walschaerts, piston valves |
| Fueltype: | Coal |
| Fuelcap: | C1, 7LT C1a, 6LT |
| Watercap: | C1, 4000impgal C1a 3510impgal |
| Locoweight: | C1, 122LT C1a, 128LT |
| Length: | 74feet |
The CGR class C1 and C1a were steam locomotives of the Garratt type built by Beyer, Peacock & Company, England for the Ceylon Government Railways (CGR), now Sri Lanka Railways. The Class C1 prototype was built in 1928 and was followed by eight Class C1a locomotives in 1946. The C1a class was converted to oil firing between 1950 and 1954.[1]
Dimensions are shown in the table (right). Particulars of the boilers are not known but it is likely that the C1a had a significantly bigger boiler than the C1. The evidence for this is that the C1a was 61NaN1 tons heavier than the C1, although it carried 12NaN2 less fuel and about 22NaN2 less water.