List of quarries served by the Ffestiniog Railway The quarries The quarries

| Name_ | Mineral | Opened | Closed | Years_connected | Notes_ |
|---|---|---|---|---|---|
| Cwmorthin | Slate | 1810 | 1937 | 1850–1937 | Connected via the Cwmorthin Tramway; became part of the Oakeley quarry in 1900, the two quarries were connected underground |
| Cwt-y-Bugail | Slate | 1835 | 1972 | 1867–1961 | Last quarry using the (by then partly lifted) Rhiwbach Tramway |
| Diphwys Casson | Slate | 1760 | 1972 | 1860–1955 | Last of the major quarries to be connected to the Ffestiniog Railway |
| Graig Ddu | Slate | 1840 | 1946 |  | Connected via the Festiniog and Blaenau Railway |
| Groby Granite | Granite | 1901 | Circa 1932 | 1914-c.1932 | Connected by a short, steeply graded branch worked by FfR locomotives. |
| Hafodty (Votty) | Slate | 1801 | 1870 | 1851–1870 | Joined with Bowydd quarry to form Votty & Bowydd |
| Llechwedd | Slate | 1846 | Present | 1848-1980s | Currently worked on a small scale and the site of the Llechwedd Slate Caverns tourist attraction |